Question

Mikayla evaluated the expression 0.86 × 23.4 using the steps shown below.

0.86
× 23.4
344
2580
+ 17200
= 201.24

Which best explains mikayla's error?

A. Mikayla added the whole numbers incorrectly.
B. Mikayla multiplied the whole numbers incorrectly.
C. Mikayla moved the decimal incorrectly.
D. Mikayla's answer should have been a while number.

Answer 1

C. Mikayla moved the decimal incorrectly.

The decimal should have been moved 3 spaces, to get an answer of 20.124

Answer 2

Mikayla moved the decimal incorrectly.

Explanation:

mikayla evaluated the expression 0.86 × 23.4 using the steps shown below.

0.86

× 23.4

344

2580

+ 17200

= 201.24

LEts do the multiplication without decimals

8 6

x 2 3 4

--------------------

3 4 4

2 5 8 0

1 7 2 0 0

------------------------------

2 0 1 2 4

0.86 has two numbers after the decimal point and 23.4 has one number after the decimal point

So we move 3 places to the left ( 20.124)

Mikayla moved the decimal incorrectly.