The average weight of ‘x’ persons is 64 kg. The average weight of (x – 20) women is 60 kg, the average weight of (x – 30) children is 55 kg, and the average weight of (x – 34) men is 60 kg. Find the value of ‘x’, if total person is the sum of men, women and children.
Total weight of x persons = 64 × x = 64x kg Total weight of (x – 20) women = 60 × (x – 20) = 60x – 1200 kg According to the question, 64x = 60x – 1200 + 55x – 1200 + 60x – 2040 64x = 175x – 4440 111x = 4440 x = 40
Four persons ‘A’, ‘B’, ‘C’ and ‘D’ have different amounts with them. ‘D’ has twice amount than that of ‘A’. The amount ‘B’ has is 12.5% more than that of ‘D’. The amount ‘C’ has is equal to the average amount all four persons have. If the sum of the average amount all four have and the amount ‘A’ has is Rs. 220, then find the amount ‘B’ has.
Let ‘A’ has Rs. a Therefore, amount possessed by ‘D’ = Rs. 2a Amount possessed by ‘B’ = 1.125 × 2a = Rs. 2.25a Let the average amount possessed by all four be Rs. x Therefore, amount possessed by ‘C’ = Rs. x Sum amount possessed by all four be Rs.4x According to the question, 2.25a + 2a + a = 4x – x Or, 5.25a = 3x Or, x/a = 7/4 Therefore, a = 220 × 4/11 = Rs. 80 Amount possessed by ‘B’ = 2.25a = Rs. 180
In an aptitude exam for a company, there are certain average marks. After recovering quantitative mistakes, the average marks of 130 students got decreased from 80 to 48 and the average marks of all the students is decreased by 20 marks. Find the total number of students.
Let average marks be N. Total marks of 130 students = 80 × 130 = 10400 After recovering quantitative mistakes, Total marks of 130 students = 48 × 130 = 6240 Average marks are reduced by = 20 Total number of students in an exam = (10400 - 6240)/20 = 208 ∴ Required number of students = 208
Piyush on his birthday distributed on an average 20 toffees per student. If on the arrival of the teacher and the headmaster to whom Piyush gave 25 and 30 toffees respectively, the average toffee distributed per head increases to 20.5, then what is the number of students among whom the toffees were distributed?
Let’s assume that initial number of students be x. ∴ Number of toffees given to x students = 20x After the arrival of teacher and headmaster, total toffees distributed = 20x + 25 + 30 = 20x + 55 Now, the average becomes 20.5, ∴ 20x + 55 = 20.5 × (x + 2) ⇒ 20x + 55 = 20.5x + 41 ⇒ x = 28 ∴ The number of students among whom the toffees were distributed is 28.
Four persons ‘A’, ‘B’, ‘C’ and ‘D’ have different amounts with them. ‘D’ has twice amount than that of ‘A’. The amount ‘B’ has is 12.5% more than that of ‘D’. The amount ‘C’ has is equal to the average amount all four persons have. If the sum of the average amount all four have and the amount ‘A’ has is Rs. 1100, then find the amount ‘B’ has.
Let ‘A’ has Rs. a Therefore, amount possessed by ‘D’ = Rs. 2a Amount possessed by ‘B’ = 1.125 × 2a = Rs. 2.25a Let the average amount possessed by all four be Rs. x Therefore, amount possessed by ‘C’ = Rs. x According to the question, 2.25a + 2a + a = 4x – x Or, 5.25a = 3x Or, x/a = 7/4 Therefore, a = 1100 × 4/11 = Rs. 400 Amount possessed by ‘B’ = 2.25a = Rs. 900