### Home > CC1 > Chapter 8 > Lesson 8.1.4 > Problem8-53

8-53.

Maciel and Alejandro were trying to figure out the answer to $8.42+0.3$. Maciel thinks the answer is $8.72$, but Alejandro got $8.45$. Who is correct? Why? What did the other person do wrong?

Think about the meaning of $0.3$. Does it mean $3$ tenths? $3$ hundreths? $3$thousandths? Which part of $8.42$ has the same place value?

$0.3$ means $3$ tenths. $8.42$ means $8$ wholes, $4$ tenths, and $2$ hundreths. Can you combine these values now?

Maciel is correct. Can you explain how Alejandro found the wrong sum?