Question

Sydney applied the steps below to find the product of (3.1)(–1.6).

Step 1: (3.1)(–1.6) = (–1.6)(3.1)
Step 2:                   = _______________
Step 3:                   = (–4.8) + (–0.16)
Step 4:                   = –4.96

Which expression correctly fills in the blank in Step 2?
(1.6)(3) – (1.6)(0.1)
(–1)(3) + (–0.6)(0.1)
(1)(3) – (0.6)(0.1)
(–1.6)(3) + (–1.6)(0.1)

Answer 1

to get the numbers in step 3

multiply -1.6 by 3

then multiply -1.6 by 0.1

and add them together

answer is D) (–1.6)(3) + (–1.6)(0.1)

Answer 2

In Step 2 the expression is Option 4 is correct.

Explanation:

Given : Sydney applied the steps below to find the product of
`(3.1)(-1.6)`.

To find : Which expression correctly fills in the blank in Step 2?

Solution :

Step 1 : Commutative property applied,
`ab=ba`

`(3.1)(-1.6)=(-1.6)(3.1)`

Step 2 - Apply distributive property
`a(b+c)=ab+ac` by re-write 3.1=3+0.1

`(3.1)(-1.6)=(-1.6)(3+0.1)`

`(3.1)(-1.6)=(-1.6)(3)+(-1.6)(0.1)`

Step 3 - Solve the multiple,

`(3.1)(-1.6)=(-4.8)+(-0.16)`

Step 4 - Add the terms,

`(3.1)(-1.6)=-4.96`

Therefore, In Step 2 the expression is Option 4 is correct.