If 15 men can dig a trench 35 m long in 1 day, then how many men can dig a similar trench 84 m long in 1 day ?

The ratio between 6 cm and 20 mm is

1. 3 : 1
2. 3 : 10
3. 6 : 10
4. 3 : 2

If A : B = 2 : 5 and B : C = 4 : 5, then C : A = ?

1. 5 : 2
2. 2 : 1
3. 15 : 8
4. 25 : 8

By increasing 91 in the ratio 7 : 13, we get :

1. 182
2. 169
3. 121
4. 116