Question

16. An army of 300 soldiers has provision for 14 weeks. After 7 weeks
50 more soldiers join the camp. The number of weeks use the
provision will last is :
A) 13
B) 12
C) 11 D) 10.5
Ans. A) 13​

Answer 1

This can be done using unitary method .

Solution :

An army of 300 soldiers has provision for 14 weeks.

After 7 weeks pass ;

An army of 300 soldiers has provision for another 7 weeks .

One soldier will have enough provision for

> 300 × 7 weeks

> 2100 weeks.

Now , 50 more soldiers join the camp .

Total number of soldiers becomes :

> 300 + 50

> 350

Then number of weeks the provisions will last :

> 2100/350

> ( 210/35 )

> 6

So , the provision will last for another 6 weeks.

Total number of weeks the provision lasted

> 7 w + 6w

> 13 weeks .

Hence , option A is the required answer.

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