Question

which shows the correct expression and answer for solving 1.8 x 1.2 with partial products?

1 + 0.08 + 0.02 + 0.16; 1.26
1 + 0.8 + 0.2 + 1.6; 2.16
1 + 0.08 + 0.2 + 0.16; 1.26

Answer 1

To solve \( 1.8 \times 1.2 \) using partial products, we can break down the numbers into their whole and decimal parts. Here's how it works:

\( 1.8 \) can be broken down into \( 1 + 0.8 \) and \( 1.2 \) can be broken down into \( 1 + 0.2 \).

Now we calculate the partial products:

1. \( 1 \times 1 = 1 \)
2. \( 1 \times 0.2 = 0.2 \)
3. \( 0.8 \times 1 = 0.8 \)
4. \( 0.8 \times 0.2 = 0.16 \)

Now add all the partial products together:

\[
1 + 0.2 + 0.8 + 0.16 = 1 + 0.2 + 0.8 + 0.16 = 2.16
\]

So the correct expression and answer using partial products for \( 1.8 \times 1.2 \) is:

**1 + 0.8 + 0.2 + 1.6; 2.16**

Thus, this option:

**1 + 0.8 + 0.2 + 1.6; 2.16**

is the correct choice.