Question
The average number of novels on historical, thriller and
fantasy in a library is 170, and the average number of novels on historical and fantasy is 140. 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 = 170 => x + y + z = 510 ….. (1) And, (x + z)/2 = 140 => x + z = 280 ….. (2) From equation 1 and 2 Number of novels on thriller = y = 230 Number of novels on fantasy = 0.8 × 230 = 184 Therefore, number of novels on historical = 510 – (230 + 184) = 96
3. 8, 15, 24, 34, 48, 63
Select the wrong term in the series.
44, 47, 41, 50, 38, 53, 40
Select the wrong term in the series.
10, 19, 23, 52, 61, 133, 149
Find the wrong number in the following number series:
2500, 1000, 400, 160, 60
A series is given with one wrong term. Select the wrong number from the given series.
17, 29, 43, 59, 77, 97, 112
8, 20, 48, 108, 232, 482
In this question, one term in the number series is wrong. Find out the wrong term.
130, 135, 143, 154, 168, 183, 205
Find the wrong number.
17, 25, 37, 47, 65, 81
Arrange the following words in a logical and meaningful order.
1. Monkey
2. Elephant
3. Rat
4. Fly
5. Lion
Select the number from among the given options that is wrong in the following series.
22, 30, 46, 78, 146, 270
