Question
There are 7 people in a group. Average age of the group
decreases by 5 when two more people join the group. Find the average age of the new group. Statement I: Sum of the ages of the two people who joined later is 25 yrs. Statement II: Total of the ages of people originally was 245 yrs. In each of the following questions, a question is followed by two statement. Read all the statements and find that which statements are required to answer the question and answer accordingly.Solution
From statement I: People becomes 9 from 7, and average decreases by 5. Let ‘n’ is previous average and then ‘n - 5’ is new average. So Sum of ages of 2 new people becomes 9 × (n – 5) – 7 × n which is given 25 So 9 × (n – 5) – 7 × n = 25 So 9n – 45 – 7n = 25 or 2n = 25+45= 70 So, n = 70/2 = 35 So average of new group = 35 – 5 = 30 From statement II: Total age of 7 people is 245 years, so their average = 245/7 = 35 So, average of new group = 35 – 5 = 30 So answer can be determined by either of statement I or II.
The ages of A, B and C are in the ratio of 5:3:7 respectively. If the sum of their ages is 60 years, then find the age of B.
A sum of ₹12,000 is divided among A, B, and C in the ratio 3:4:5. If A and B donate 25% and 20% of their shares respectively to a charity, how much mo...
If a/b =c/d =e/f =2/3 Then (2a2-3c2+4e2)/ (2b2-3d2+4f2) =?
The ratio of two numbers A and B is 9:19 and C is 60% of the average of the numbers A and B. If the sum of A, B and C is 182, then what is the value of A?
The ratio of the incomes of Vineet and Vidya is 12:7 respectively. Vineet saves 25% of his income while Vidya saves 20% of his income. The sum of their ...
An amount is distributed among P, Q, R, and S in the ratio 12:8:5:6 respectively. If the amount received by Q is Rs. 1,600 , then find the amount receiv...
Three numbers are in ratio 2:3:5. If the sum of the squares of those three numbers is 342 then find the sum of the three numbers.
The cost of diamond varies directly as the square of its weight. A diamond broke into four pieces with weights in the ratio 2 : 3 : 5 : 6. if the loss i...
Two numbers are in the ratio 6:5. After adding 3 and 5 to them respectively the ratio becomes 2:3. Find the bigger number.
Three numbers are in ratio 3:4:7. If the sum of the squares of those three numbers is 666 then find the sum of the three numbers.
Relevant for Exams:
