Rasel can fill advertising circulars into envelopes at the rate of 45 envelopes per minute and Ali requires a minute and a half to fill the same number of envelopes. Working together, how long will it take Rasel and Ali to fill 300 envelopes?

Question: Rasel can fill advertising circulars into envelopes at the rate of 45 envelopes per minute and Ali requires a minute and a half to fill the same number of envelopes. Working together, how long will it take Rasel and Ali to fill 300 envelopes?Solution:Given,Rasel can fill 45 envelopes in 1 minutesand,Ali can fill 45 envelopes in (1 + 1/2) = 3/2 minutesSo Ali can fill in 1 minutes = (45 ÷ 3/2) envelopes= (45 × 2/3) envelopes= 30 envelopesSo Rasel and Ali together can fill in 1 minutes = (45 + 30) = 75 envelopes∴ 75 envelopes can fill in 1 minutes∴ 1 envelopes can fill in 1/75 minutes∴ 300 envelopes can fill in (1 × 300)/75 minutes= 4 minutes