24. Send It Out mails advertisements for businesses. Two types of machines—stuffing machines and postage machines－are used to process envelopes. Each stuffing machine processes envelopes at the rate of 150 envelopes per minute, and each postage machine processes envelopes at the rate of 4 envelopes per second. Send It Out is currently using 24 stuffing machines. How many postage machines should be used so that the stuffing machines and the postage machines process the same number of envelopes in 1 minute ?

Answer and Explanation

Your Answer is

Correct Answer is H

Explanation

Each stuffing machine can process 150 envelopes per minute. Each postage machine processes 4 emails per second, which means 240 emails per minute. Because there are 24 stuffing machines in total, it can process 150×4=3600 pieces per minute. You need 3600÷240=15 postage machines