### Home > MC1 > Chapter 9 > Lesson 9.1.2 > Problem9-19

9-19.

Simplify each of the following expressions without a calculator, and then use a calculator to check your answers.

1. $0.045 + 1.2 + 62.003$

Make sure you add the parts that are like.
You can think of $0.045$ as

$\frac{4}{100}\text{ and } \frac{5}{1000}\text{ or is }\frac{45}{1000}.$

How can you combine this with the other numbers?
Be sure to show your work.

1. $56.7 - 0.23$

You can think of $56.7$ as $56\frac{7}{10}$  and $0.23$ as  $\frac{23}{100}$.

How can you subtract $23$-hundredths from $70$-hundredths?

1. $\left(7.8\right)\left(0.03\right)$

$0.234$

1. $6.3 - 7.5$

Since $7.5$ is greater than $6.3$, your answer should be less than zero.

$−1.2$