All SAT Math Resources
Example Questions
Example Question #5 : Decimals
45.728 x 3.2 = ?
14632.96
14.63296
146.3296
1463.296
146329.6
146.3296
Multiply the numbers out in long format, then move the decimal point over the total number of decimal points in the two numbers (3 in the first, 1 in the second, so 4 total):
45.728 * 3.2 = 91456
91456 + 1371840 = 1,463,296 → 146.3296
Or just count the decimal points in the answer and make sure it's 4.
Example Question #1 : How To Multiply Decimals
At the farmer's market, oranges are $0.30 each, apples are $0.25 each, bananas are $0.40 each, and tomatoes are $0.60 each. If Scott buys 3 oranges, 7 apples, 4 bananas, and 8 tomatoes, how much does he spend?
$7.75
$11.40
$6.80
$10.40
$9.05
$9.05
To find out how much Scott spends, we need to multiply the quantity of each fruit by its price and add them all up.
3 * $0.30 + 7 * $0.25 + 4 * $0.40 + 8 * $0.60 = $9.05
Example Question #2 : How To Multiply Decimals
If is 25% of , what is the closest integer to the value of ?
We can approximate the value of y pretty quickly:
y ≈ 1(0.50)(52) = 26
Since y = 0.25x = (1/4)x we know that x = 4y ≈ 4(26) = 104
Example Question #3 : How To Multiply Decimals
0.006
0.6
0.06
0.0006
6
0.006
It's much easier to work with whole numbers, so we'll ignore the decimals for the first step: 5 x 12 = 60
Now look at the decimals. To add them back in, think of 60 as 60.0. Now move the decimal point four places to the left: 0.5 x 0.012 = .0060 = .006
Example Question #3 : How To Multiply And Divide Decimals
You bought a dozen eggs marked at and received change from . What is the percent of sales tax?
Set the equation up as
Solve for , which equals
or
Therefore the percent sales tax is: