Question

Myra is evaluating the expression –31.7 + 4.5x, when x = 2.1.

–31.7 + 4.5(2.1)
    –27.2(2.1)
    –57.12
What was Myra’s error?
Myra should have multiplied -31.7 and 2.1 first.
Myra should have multiplied 4.5 and 2.1 first.
Myra should have subtracted -27.2 and 2.1 first.
Myra should have added -31.7 and 2.1 first.

Answer 1

B.Myra should have multiplied 4.5 and 2.1 first.

Explanation:

We are given that Myra is evaluating the expression

-31.7+4.5 x when x=21.

We have to find the error in Myra's calculation

When x=2.1

-31.7+4.5(2.1)

-31.7+9.45

=-22.25

By using DMAS rule

D=Divide

M=Multiply

A=Addition

S=Subtraction

But Myra first add -3.7 to 4.5 then multiply

Hence, Myra should have multiplied 4.5 and 2.1 first instead of add.

Answer:B.Myra should have multiplied 4.5 and 2.1 first.

Answer 2

–31.7 + 4.5x, when x = 2.1.

-31.7 + 4.5(2.1)

-31.7 + 9.45

Myra should have multiplied 4.5 and 2.1 first.