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Dividing Decimals Dividend (in the box) Find the quotient of 12 ÷ Divisor (out of the box) 4 quotient 3 divisor dividend Set it up 4 12 -12 0 Find the quotient of 156 ÷ 12 13 12 156 -12 36 -36 0 Dividing a whole number by a whole number We are able to divide these numbers because the divisors are whole numbers! divisor 3 4 12 -12 0 divisor 13 12 156 -12 36 -36 0 Sometimes, we have to do a little more………………….. Dividing a whole number by a DECIMAL What if the divisor is NOT a whole number?? Example: Set it up The divisor is NOT a whole number! 156 ÷ 1.2 1.2 156 We have to change the divisor to a whole number by moving the decimal to the right (which is the same thing as multiplying by a power of 10) (x 10, x 100, x 1000, etc.) Dividing a whole number by a DECIMAL Example: We have to change the divisor to a whole number by moving the decimal to the right. 156 ÷ 1.2 1.2 156• 0 • • We had to move the decimal 1 place to the right, to make the divisor a whole number We have to move the decimal the same number of places in the dividend also! (1 place) 12. 1560. Dividing a whole number by a DECIMAL 130 12. • Bring the decimal 1560. straight up to the quotient. -12 36 -3 6 0 0 - 0 0 Now, you are ready to divide! Now, CHECK IT by multiplying! 130 X 1.2 260 +1 3 0 0 1 5 6•0 Dividing a DECIMAL by a DECIMAL Find the quotient 1.56 ÷ 1.2 1•3 1.2• 156 . • -12 36 -3 6 0 Bring the decimal straight up to the quotient. Now, you are ready to divide! Now, CHECK IT by multiplying! 1.3 X 1.2 26 +1 3 0 1•5 6 Dividing a DECIMAL by a DECIMAL Find the quotient 15.6 ÷ .12 1 3 0• .12• 15.6 0 • -12 36 -3 6 00 -0 0 0 Bring the decimal straight up to the quotient. Now, you are ready to divide! Now, CHECK IT by multiplying! 130 X .12 260 +1300 1560 • Dividing Decimals • Change the divisor to a whole number by moving the decimal to the right. • Move the decimal the same number of places in the dividend • If you don’t have to move the decimal in the divisor, you don’t move it in the dividend either! • Bring the decimal straight up to the quotient • Divide • Check your solution by multiplying!