Question

army camp of 1400 men have food for 18 days at a scale of 396 gram for men day how many men should be leave the camp so that the same food may last for 21 days at the scale of 432 grams for men per day​

Answer 1

Answer: 100 men

Step-by-step explanation:

the number of men and days are inversely related.

let "x" men leave the camp.

so, 1400 : 1400 - x : : 21 : 18 ....(1)

the scale and the number of days are directly related.

396 : 432 : : 18 : 21

432 : 396 : : 21 : 18 ..... (2)

combining the equations (1) and (2), we get

1400 : 1400 - x : : 21 : 18

432 : 396 : : 21 : 18

1400 x 432 x 18 = (1400 -x) x 396 x 21

1400 x 12 x 6 = (1400 - x ) x 11 x 7

1400/1400 - x = 77/ 72

(1400 x 72) = (1400 x 77) -77x

77x = 1400 x 5

x= 1000/ 11 = 90.99 = 100

hence 100 men should leave the camp.