After traveling 70 m in its dive, the submarine is at a depth of 25 m. What will the submarine’s depth be if it continues its dive for another 110 m? (NOTE: The total length of the dive is MORE than 110m!)

Assuming that the submarine is travelling at a constant rate, then we can use the information provided and apply a Rule of Three since it is basically a ratio problem. In this rule, you simply need to multiply the diagonal values of the ratio and divide by the last value to get the variable, which would be the depth after 110m

70min <=======> 25 m

110min <=======> x m

(110 * 25) / 70 = x

2750 / 70 = x

39.28 = x

We can see that at 110min the depth would be 39.28 m but since this is an additional period of time that the submarine travelled we need to add this distance to the initial 25 m to get the total depth of the submarine.

39.28m + 25m = 64.28m