Question
My grandfather’s age was seven times older to me
14 years ago. He would be two times of my age seven years from now. Seven years ago, what was the ratio of the age to that of my grandfather?Solution
Let my age 14 years ago be x years My grandfather’s age at that time = 7x years My present age = (x+ 14) years My grandfather’s present age = (7x+ 14) years 2(x+ 14 + 7) = (7x + 14 + 7) 2x + 42 = 7x + 21 5x = 21 x = 21/5 Seven years ago, ratio of ages => (x+14-7)/(7x+14-7) = (x+7)/(7x+7) => (21/5+7)/(7 × 21/5+7) = (56/5)/(182/5) = 56: 182 => 4:13
A girl found the answer for the question “subtract the sum 1/2 and 1/8 from unity and express the answer in decimals” as 1.5. The percentage...
Two boys are on opposite sides of a tower of 100 m height. If they measure the elevation of the top of the tower as 30° and 45° respectively the...
Find the H.C.F OF ( 1179 + 1379)and (1385 + 1185 )
The ratio of two number is 6 : 5 and their HCF is 15. So find and their LCM?
The efficiency of A,B,C,D are in the ratio of 6:5:4:3. If A and C can do a work together in 6 days. Then How many days B and D will take to complete the...
If x+ 1/x = 3, then find the value of 2x/(3x²-5x+3)
In a Mixture , the ratio of Milk and Water is 7 : 5. If 12 litre mixture is drawn off and replaced by 8 litre water then the ratio of Milk and Water bec...
The diameter of the base of a cylindrical drum is 21 dm and the height is 12 dm. It is full of petrol. How many tins each of size 15 cm × 11 cm &t...
If 4x + 1/5x = 4, then find value of 125x³ + 1/64x³
When N is divided by 5 the remainder is 2. What is the remainder, when n³ is divided by 5?