# Boat and Stream Aptitude Questions and Answers:

#### Overview:

 Questions and Answers Type: MCQ (Multiple Choice Questions). Main Topic: Quantitative Aptitude. Quantitative Aptitude Sub-topic: Time Speed and Distance Aptitude Questions and Answers. Number of Questions: 10 Questions with Solutions.

1. A boat goes downstream at the speed of $$25 \ km/hr$$. If the speed of stream is $$12 \ km/hr$$, then find the speed of boat in still water?

1. $$11 \ km/hr$$
2. $$12 \ km/hr$$
3. $$13 \ km/hr$$
4. $$14 \ km/hr$$

Answer: (c) $$13 \ km/hr$$

Solution: Given, speed of downstream $$(D_s) = 25 \ km/hr$$

speed of stream $$(S_s) = 12 \ km/hr$$

then speed of boat in still water, $$B_s = D_s - S_s$$ $$B_s = 25 - 12 = 13 \ km/hr$$

1. A swimmer goes downstream with the, speed of stream $$14 \ km/hr$$. If speed of the swimmer in still water is $$28 \ km/hr$$, then find the speed of downstream?

1. $$40 \ km/hr$$
2. $$42 \ km/hr$$
3. $$44 \ km/hr$$
4. $$45 \ km/hr$$

Answer: (b) $$42 \ km/hr$$

Solution: Given, speed of stream $$(S_s) = 14 \ km/hr$$

speed of swimmer in still water $$(B_s) = 28 \ km/hr$$

then speed of downstream, $$B_s = D_s - S_s$$ $$28 = D_s - 14 = 42 \ km/hr$$

1. A boat goes downstream with the speed of $$40 \ km/hr$$. If the speed of boat in still water is $$30 \ km/hr$$, then find the speed of stream?

1. $$10 \ km/hr$$
2. $$12 \ km/hr$$
3. $$13 \ km/hr$$
4. $$14 \ km/hr$$

Answer: (a) $$10 \ km/hr$$

Solution: Given, speed of downstream $$(D_s) = 40 \ km/hr$$

speed of boat in still water $$(B_s) = 30 \ km/hr$$ then, $$B_s = D_s - S_s$$ $$30 = 40 - S_s$$ $$S_s = 10 \ km/hr$$

1. A girl swims $$30 \ km$$ downstream in $$1 \ hour$$. If the speed of stream is $$5 \ km/hr$$, then find the speed of the girl in still water?

1. $$20 \ km/hr$$
2. $$22 \ km/hr$$
3. $$25 \ km/hr$$
4. $$27 \ km/hr$$

Answer: (c) $$25 \ km/hr$$

Solution: Given, speed of downstream $$(D_s) = \frac{30}{1} = 30 \ km/hr$$

speed of stream $$(S_s) = 5 \ km/hr$$

then speed of girl in still water, $$B_s = D_s - S_s$$ $$B_s = 30 - 5 = 25 \ km/hr$$

1. A boat goes upstream with the speed of $$18 \ km/hr$$. If speed of stream is $$5 \ km/hr$$, then find the speed of boat in still water?

1. $$23 \ km/hr$$
2. $$22 \ km/hr$$
3. $$21 \ km/hr$$
4. $$20 \ km/hr$$

Answer: (a) $$23 \ km/hr$$

Solution: Given, speed of upstream $$(U_s) = 18 \ km/hr$$

speed of stream $$(S_s) = 5 \ km/hr$$

then speed of boat in still water, $$B_s = U_s + S_s$$ $$B_s = 18 + 5 = 23 \ km/hr$$

1. A boat goes $$70 \ km$$ upstream, taking $$2 \ hours$$. If the speed of stream is $$20 \ km/hr$$, then find the speed of boat in still water?

1. $$52 \ km/hr$$
2. $$53 \ km/hr$$
3. $$54 \ km/hr$$
4. $$55 \ km/hr$$

Answer: (d) $$55 \ km/hr$$

Solution: Given, speed of upstream $$(U_s) = \frac{70}{2} = 35 \ km/hr$$

speed of stream $$(S_s) = 20 \ km/hr$$

then speed of boat in still water, $$B_s = U_s + S_s$$ $$B_s = 35 + 20 = 55 \ km/hr$$

1. If a boat goes $$12 \ km$$ downstream in $$36 \ minutes$$ and the speed of boat in still water is $$8 \ km/hr$$, then find the speed of stream?

1. $$10 \ km/hr$$
2. $$12 \ km/hr$$
3. $$13 \ km/hr$$
4. $$15 \ km/hr$$

Answer: (b) $$12 \ km/hr$$

Solution: Given, speed of downstream $$(D_s) = \frac{12}{36} \times 60 = 20 \ km/hr$$

speed of boat in still water $$(B_s) = 8 \ km/hr$$

then speed of stream, $$B_s = D_s - S_s$$ $$8 = 20 - S_s$$ $$S_s = 12 \ km/hr$$

1. If a man can swim upstream at the speed of $$7 \ km/hr$$ and speed of stream is $$3 \ km/hr$$, then find the speed of man in still water?

1. $$15 \ km/hr$$
2. $$13 \ km/hr$$
3. $$12 \ km/hr$$
4. $$10 \ km/hr$$

Answer: (d) $$10 \ km/hr$$

Solution: Given, speed of upstream $$(U_s) = 7 \ km/hr$$

speed of stream $$(S_s) = 3 \ km/hr$$

then speed of the man in still water, $$B_s = U_s + S_s$$ $$B_s = 7 + 3 = 10 \ km/hr$$

1. A women can swim $$18 \ km$$ downstream in $$10 \ minutes$$. If the speed of stream is $$80 \ km/hr$$, then find speed of the women in still water?

1. $$28 \ km/hr$$
2. $$25 \ km/hr$$
3. $$24 \ km/hr$$
4. $$22 \ km/hr$$

Answer: (a) $$28 \ km/hr$$

Solution: Given, speed of downstream $$(D_s) = \frac{18}{10} \times 60 = 108 \ km/hr$$

speed of stream $$(S_s) = 80 \ km/hr$$

then speed of the women in still water, $$B_s = D_s - S_s$$ $$B_s = 108 - 80 = 28 \ km/hr$$

1. A boat goes upstream with the speed of $$30 \ km/hr$$. If the speed of boat in still water is $$45 \ km/hr$$, then find the speed of stream?

1. $$12 \ km/hr$$
2. $$13 \ km/hr$$
3. $$14 \ km/hr$$
4. $$15 \ km/hr$$

Answer: (d) $$15 \ km/hr$$

Solution: Given, speed of upstream $$(U_s) = 30 \ km/hr$$

speed of boat in still water $$(B_s) = 45 \ km/hr$$

then speed of stream, $$B_s = U_s + S_s$$ $$45 = 30 + S_s$$ $$S_s = 15 \ km/hr$$