Question

Gena and her friends each estimated the quotient of –137.56 divided by –6.12 using compatible numbers. Which shows the best estimate using compatible numbers?

Answer 1

Answer:

23

Step-by-step explanation:

Compatible numbers : numbers that are easy to add, subtract, multiply, or divide mentally.  They are close in value to the actual numbers, although they do not necessary need to be rounded numbers.

-138 is close to -137.56

-6 is close to -6.12

$\implies \dfrac{-138}{-6}$

Divide the top and bottom by -2:

$\implies \dfrac{69}{3}$

Divide the top and bottom by 3

$\implies 23$

If this is too difficult to divide mentally, you could use -140 and -7:

$\implies \dfrac{-140}{-7}$

As 2 x 7 = 14, then 20 x 7 = 140, so the answer is 20.