For multiplication, just break it down into small bits in pieces, especially easy numbers like 2, 3, 5, 10, and 12. And then just multiply those instead. If needed, you can also use this: ac + bc = c(a+b)
For example, 12 * 320 = 12 * 4 * 8 * 10, which is 48 * 8 * 10. Okay now, you have to multiply 48 and 8! Then you break that down. 48 * 8 = (40 * 8) + (8 * 8).
That is 320 + 64, or 384. Then multiply that by 10. You get 3840! It may take some practice, but when you succeed, you will be amazing!
I have to say, pretty much the same for division.
Divide the numerator by the denominator
How about using a calculator!
Multiply by 0.9144
Multiply both numbers by five- to get the fraction 85/100... which is 85%
You multiply the number together - using a calculator if needed.
Divide the numerator by the denominator
Multiply the numerator of the fraction by 100 and then divide (using long division if needed or a calculator) by the denominator.
% rate:1. Divide 17 by 20.2. Multiply the quotient by 100%= (17 ÷ 20) x 100%= 0.85 x 100%= 85%
by using a calculator
How about using a calculator!
with your brain... Or the old-fashioned way -by counting it out on your fingers.
Multiply the whole number times the numerator. Divide the product by the denominator.
you divide 3 by 5 :P
Multiply by 0.9144
Two choices: -- Multiply (the number) x (the percent using the percent % key). -- Multiply (the number) x (the percent), then divide the answer by 100. Either way, the claculator displays that many percent of that number.
To find a percentage using a calculator, you would simply multiply the number by the percentage you are looking for and then divide by 100. For example, to find 20% of 50, you would enter 50 x 20 รท 100 = 10.
Multiply both numbers by five- to get the fraction 85/100... which is 85%