Question
The average number of novels on historical, thriller and
fantasy in a library is 195, and the average number of novels on historical and fantasy is 150. If the number novels on fantasy is 20% less than the number of novels on thriller, then what is the number of novels on historical in the library?Solution
Let the number of novels on historical, thriller and fantasy be x, y and z respectively. Given, (x + y + z)/3 = 195 => x + y + z = 585 ….. (1) And, (x + z)/2 = 150 => x + z = 300 ….. (2) From equation 1 and 2 Number of novels on thriller = y = 285 Number of novels on fantasy = 0.8 × 285 = 228 Therefore, number of novels on historical = 585 – (285 + 228) = 72
If x2 – xy + y2 = 16 and x4 + x2y2 + y4 = 320 then find x2 + xy + y2...
If [2a + (1/2a)] = 5, then find the value of [4a² + (1/4a²) - 6]
When 732 is divided by a positive integer x, the remainder is 12. How many values of x are there?
If x = 15, find x5 - 16x4 + 16x3 - 16x2 + 16x - 16 = ?
The roots of the quadratic equation x² + px + q = 0 are in the ratio 3:4. If the sum and product of the roots are 7 and 12, respectively, find the valu...
Solve: 1/x + 1/y = 5/2 and 1/x – 1/y = 1/6
A boat covers 540 km upstream and downstream in 't' time. If the speed of the stream is 8 km/h and the speed of the boat is 10 km/h then find the value ...
If 2x + 4y - 9 = 0, then find the value of 8x 3 Â - 723 + 64y 3 Â + 216xy.
Solve for x in the equation: 3(x + 2) + 2(2x - 5) = 5x + 9
Relevant for Exams:
