ffirs.indd

(Brent) #1

158 Speed Math for Kids
Th ree won’t divide into 1 so we divide the fi rst two digits by 3.
Th ree divides into 19 six times with 1 remainder (6 × 3 = 18). Th e
1 is carried to the next digit of the dividend (the number we are
dividing), which makes 15.
32
–2
6
30 19.^15
Before we divide into 15 we adjust for the 2 in 32. We multiply
the last digit of the answer, 6, by the units digit in the divisor, 32,
which is 2.
6 × 2 = 12
We subtract 12 from the working number, 15, to get 3.
What we have done is multiplied 32 by 6 and subtracted the answer
to get 3 remainder. How did we do this?
We subtracted 6 times 32 by fi rst subtracting 6 times 30, then 6
times 2. Th is is really a simple method for doing standard long
division in your head.
32
–2
6 r3
30 19.^15
Let’s try another one. Let’s divide 430 by 32 to 2 decimal places. We
set up the problem like this:
32
–2
30 430
We divide both numbers by 10 to get 3 and 43. We add three zeros
after the decimal so that we can calculate the answer to two decimal

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