If a boat travels at a speed of 20 km per hour in stillwater. Now if it's travelling in downstream speed of 10 km per hour and travel 70 kilometre. What is the time taken by it?

Time= distance /speed

Sister boat is travelling in a downstream the speed of the stream adds up in the speed of boat so its speed=boat speed+downstream speed. which becomes 20+10=30 km/hr. Now applying the formula we get

Time=70/30 we get our answer which is 2.3

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There are three boxes A, B and C. Only one box has gold in it. Moreover only one of the statements is true
(i) The box A says he has no gold
(ii) The box B says he has no gold
(iii) The box C says B is lying
So which box has gold?

No explanation available for this question..

The average of 5 quantities is 6. The average of 3 of them is 8. What is the average of the remaining two numbers?

The average of 5 quantities is 6.

Therefore, the sum of the 5 quantities is 5 *6 = 30.

The average of the 3 of these 5 quantities is 8.

Therefore, the sum of these 3 quantities = 3*8 = 24

The sum of the remaining two quantities = 30 - 24 = 6.

Average of these two quantities = 6 / 2 = 3.

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A test has 30 questions. If Ammy gets 70% correct, how many question did Ammy missed?

The number of correct answers is 70% of 30 or 70/100 x 30.

70/100 x 30 = 21

Since the test has 30 questions and she got 21 correct answers, the number of questions she missed is 30-21=9

Ammy missed 9 questions.

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A fruit salad mixture contains Apple, peach and melon in the ratio of 3 :2:1 .If a bowl of the mixture contains 3 Peach, how much Apple does it in bowl?

Ratio of fruit salad:

Apple :peach: melon

2 : 3 : 5

3 peach than Apple:

3 / 2 = 1.5

Ration of Apple is 3 X 1.5 = 4.5

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Pointing toward a person in a photograph, Lara said "He is the only son of

the father of my sister's brother."

How is that person related to Lara?

The relations may be analyzed as follows :

Sister's brother -- Brother;

Brother's father -- Father;

Father's son -- Brother.

So, the person in the photograph is Lara's brother.

Hence, the answer is (d).

Jim who is 6 year old and his uncle Harry who is 27 year old have the same birthday. In how many years will Harry be twice as old as jim?

Let's X is year add in both age

Jim:X + 6

Harry: X + 27

When Harry be twice old jim.

2 (X + 6 )= X + 27

x = 15

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Two trains starting at the same time from two station 200 km apart and going in opposite directions cross each other at a distance of 110 km from one of the stations. What is the ratio of their speeds?

In the same day they cover 110 km and 90 km respectively.

For the same time speed and distance is inversely proportional.

Show the ratio of their speed=110:90=11:9.

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