How to multiply and divide decimals - HSPT Math
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Anita is sewing a quilt made of 120 patches. She has sewn together 84 patches already. What percentage of the quilt has Anita sewn?
Anita is sewing a quilt made of 120 patches. She has sewn together 84 patches already. What percentage of the quilt has Anita sewn?
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Divide 84 by the entire amount of patches 120 to find the percentage completed.
The answer is Anita has completed 70% of the quilt.
Divide 84 by the entire amount of patches 120 to find the percentage completed.
The answer is Anita has completed 70% of the quilt.
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Kevin is looking at the blueprint of the house he is building. The scale is 1 inch = 5 feet. On paper, the master bedroom is 2.5 inches by 3 inches. What is the actual size of the bedroom?
Kevin is looking at the blueprint of the house he is building. The scale is 1 inch = 5 feet. On paper, the master bedroom is 2.5 inches by 3 inches. What is the actual size of the bedroom?
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The given dimensions must be multiplied by 5, so 2.5 inches becomes 12.5 feet, and 3 inches becomes 15 feet.
The given dimensions must be multiplied by 5, so 2.5 inches becomes 12.5 feet, and 3 inches becomes 15 feet.
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If Exam 1 is worth 25% of the total grade, Exam 2 is worth 25% and Exam 3 is worth 50%, what is Dave’s final grade?
If Exam 1 is worth 25% of the total grade, Exam 2 is worth 25% and Exam 3 is worth 50%, what is Dave’s final grade?
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Final Grade = Exam1 * 0.25 + Exam 2 * 0.25 + Exam3 * 0.50 =
96*0.25 + 70*0.25 + 85*0.5 =
24 + 17.5 + 42.5 = 84
Final Grade = Exam1 * 0.25 + Exam 2 * 0.25 + Exam3 * 0.50 =
96*0.25 + 70*0.25 + 85*0.5 =
24 + 17.5 + 42.5 = 84
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A car has gas mileage of 46 miles per gallon. Assume that gas costs $3.90 per gallon. What would be the total cost of gas if the car traveled 1,150 miles?
A car has gas mileage of 46 miles per gallon. Assume that gas costs $3.90 per gallon. What would be the total cost of gas if the car traveled 1,150 miles?
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First find out how many gallons of gas the car consumed while traveling 1150 miles. This can be found out like so:
1150 miles x gallons/46 miles = 25 gallons
Multiplying 25 by $3.90 yields $97.50.
First find out how many gallons of gas the car consumed while traveling 1150 miles. This can be found out like so:
1150 miles x gallons/46 miles = 25 gallons
Multiplying 25 by $3.90 yields $97.50.
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If 
, approximately how many inches are in one meter?
If
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and 
Using the factor-label method we get the following equation.
We treat the units as if they are numbers, and can cancel the units from the fractions.
Using the factor-label method we get the following equation.
We treat the units as if they are numbers, and can cancel the units from the fractions.
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What is 48,570 in scientific notation?
What is 48,570 in scientific notation?
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Convert to scientific notation by creating a number that is greater than or equal to 1 AND less than 10 AND includes the same digits as the original number. Remove all zeros before the first natural number and after the last natural number.
So, we have 48,570.
Now we move the decimal to create our number between 1 and 10.
4.8570
We have one zero after the last natural number, which is 7. Remove that.
4.857
Now we must multiply that number by 10 to a certain power. We choose our power by how many places the decimal must move to get our original number. In this case, the decimal would have to move 4 places to the right.
4.857
48.57
485.7
48,570.
So our final answer is 
Convert to scientific notation by creating a number that is greater than or equal to 1 AND less than 10 AND includes the same digits as the original number. Remove all zeros before the first natural number and after the last natural number.
So, we have 48,570.
Now we move the decimal to create our number between 1 and 10.
4.8570
We have one zero after the last natural number, which is 7. Remove that.
4.857
Now we must multiply that number by 10 to a certain power. We choose our power by how many places the decimal must move to get our original number. In this case, the decimal would have to move 4 places to the right.
4.857
48.57
485.7
48,570.
So our final answer is
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You bought a dozen eggs marked at 
and received 
change from 
. What is the percent of sales tax?
You bought a dozen eggs marked at
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Set the equation up as
Solve for 
, which equals 
or
Therefore the percent sales tax is:
Set the equation up as
Solve for
or
Therefore the percent sales tax is:
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Multiply: 
Multiply:
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To multiply, there is no need to solve for a least common denominator. Simply multiply the numerator with the numerator and the denominators together.
To multiply, there is no need to solve for a least common denominator. Simply multiply the numerator with the numerator and the denominators together.
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Multiply: 
Multiply:
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Multiply the terms as is, ignoring the decimal.
Since there is one decimal from the original problem, the decimal place is one unit from the right. Therefore, the final answer must have a decimal one unit to from the right.
The answer is 
.
Multiply the terms as is, ignoring the decimal.
Since there is one decimal from the original problem, the decimal place is one unit from the right. Therefore, the final answer must have a decimal one unit to from the right.
The answer is
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Above is the menu at the concession stand at a school carnival.
David wants to buy some chicken strips for himself and his companions. He wants six strips, his brother Mickey wants five strips, his girlfriend Vickie wants three, and Mickey's girlfriend Jenny wants five. Since the concession stand only sells the strips in orders of four, he has decided to just purchase as many orders as it takes to feed the entire group. How much will he spend on enough orders of strips to satisfy the group?
(No tax is charged, since this is a school event)
Above is the menu at the concession stand at a school carnival.
David wants to buy some chicken strips for himself and his companions. He wants six strips, his brother Mickey wants five strips, his girlfriend Vickie wants three, and Mickey's girlfriend Jenny wants five. Since the concession stand only sells the strips in orders of four, he has decided to just purchase as many orders as it takes to feed the entire group. How much will he spend on enough orders of strips to satisfy the group?
(No tax is charged, since this is a school event)
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The group wants a total of 
strips; since
,
Dave will need to purchase five orders of strips (he cannot purchase a partial order). This will cost him
.
The group wants a total of
Dave will need to purchase five orders of strips (he cannot purchase a partial order). This will cost him
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An aircraft's cruising speed is 
miles per hour. How far will it travel in 
hours?
An aircraft's cruising speed is
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The formula to calculate distance is 
where 
represents rate of speed and 
represents time.
In this problem, 
mph., and 
hours.
Convert the 
to an improper fraction:
To solve, multiply.
miles.
At its cruising speed of 
mph, the aircraft will travel 
miles in 
hours.
The formula to calculate distance is
In this problem,
Convert the
To solve, multiply.
At its cruising speed of
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What is the equivalent of 
%.
What is the equivalent of
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To solve, divide: 
Answer: 
To solve, divide:
Answer:
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What is the equivalent of 
%?
What is the equivalent of
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Divide: 
Answer: 
Divide:
Answer:
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What is the equivalent of 
%?
What is the equivalent of
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Divide: 
Answer: 
Divide:
Answer:
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What is the equivalent of 
%?
What is the equivalent of
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Divide: 
Answer: 
Divide:
Answer:
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What is the equivalent of 
%?
What is the equivalent of
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Divide: 
Answer: 
Divide:
Answer:
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Myrtle gets 5 hours of sleep each night and takes a 3 hour nap every day. What percentage of the day does she spend asleep? (Round to the nearest percent.)
Myrtle gets 5 hours of sleep each night and takes a 3 hour nap every day. What percentage of the day does she spend asleep? (Round to the nearest percent.)
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Given that Myrtle takes a 3 hour nap and gets 5 hours of sleep a night, she gets 8 hours of sleep per day out of a 24 hour day. 8 hours out of 24 hours is 33%. That is therefore the correct answer.
Given that Myrtle takes a 3 hour nap and gets 5 hours of sleep a night, she gets 8 hours of sleep per day out of a 24 hour day. 8 hours out of 24 hours is 33%. That is therefore the correct answer.
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What is the equivalent of 
%?
What is the equivalent of
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To solve, divide:
Answer: 
To solve, divide:
Answer:
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What is 
written as a decimal?
What is
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Divide by 100:
Answer: 
Divide by 100:
Answer:
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Multiply: 
Multiply:
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Ignore the decimals for now and multiply 
by 
.
Since there is a decimal place one place from the right for both numbers, there will be a decimal place 2 places from the right.
The correct answer is: 
Ignore the decimals for now and multiply
Since there is a decimal place one place from the right for both numbers, there will be a decimal place 2 places from the right.
The correct answer is:
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