An Office used three types of envelopes: small,medium and large. They used 160 small envelopes. The

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07 Mar 2019 Envelopes Used

An Office used three types of envelopes: small,medium and large. They used 160 small envelopes. The no.of Medium envelopes used was 5 times the no. of small envelopes plus 5/20 of the total number of envelopes. The no. of large envelopes was equal to the no. of small envelopes plus 5/20 of the no. of medium envelope. Altogether, How many envelope did they use?

OPtion

1) 1600
2) 2280
3) 3280
4) 2640
5) 1540
6) 1280
7) 1640
8) 1840
9) 1920
10) None of these

Solution

Let the total no. of envelopes be x

No. of small envelopes = 160
No. of medium envelopes =5*160+5/20*x = 800+5/20*x
No. of large envelopes = 160 +5/20(800+5/20*x) = 360 + 25/400*x

Sum of small, medium and large envelopes = x

160 + 800 + 5/20*x + 360 + 25/400*x = x
1320 + 125/400*x = x
1320*x + 5/16 = x
=> 11/16 x = 1320
x = 1920

Correct Option: 9 Best Solution (0)