7. The least common multiple of natural numbers $a$ and $b$ is 140, and their greatest common divisor is 5. Then the maximum value of $a+b$ is $\qquad$
【Answer】Solution: According to the analysis, one of $a$ and $b$ is 140, and the other is 5, so: the maximum value of $a+b$ is $5+140=145$; hence, the answer is: 145.