Question
A was travelling from point X to point Y. He increased
his speed by 10 km/h after every hour. He reached his destination in 20 hours. If his initial speed was 25 km/h, then what was his average speed in the whole journey?Solution
Total distance travelled by A = (20/2) Γ {2 Γ 25 + (20 β 1) Γ 10} = 10 Γ (50 + 190) = 2400 km Required average speed = 2400/20 = 120 km/h
Find the geometric mean for the series given below.
31, 93, 279
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Which of the following is the greatest number that divides 72 and 119 and leaves 3 and 4 as respective remainders?
What least number must be added to 6834 to get a number exactly divisible by 18?
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A = (9/4) Γ B and C = (1/12) Γ A. If (A + B + C) = 300, then find the value of (12C β B).
In a group of three numbers first is double of second and half of third. The average of three numbers is 56. Find the difference between the first numb...