#### Answer

$3$

#### Work Step by Step

$ \log 25 +\log 40 = \log (40 \cdot 25 )$
or, $=\log (1000)$
or, $= \log 10^3$
or, $3 \log 10 = 3 \times 1 =3$

Published by
Pearson

ISBN 10:
0-13446-914-3

ISBN 13:
978-0-13446-914-0

$3$

You can help us out by revising, improving and updating this answer.

Update this answerAfter you claim an answer you’ll have **24 hours** to send in a draft. An editor
will review the submission and either publish your submission or provide feedback.