Question:A boy was asked to multiplied a certain number by `53`.He multiplied it by `35` and got his answar less than the correct one by `1206`.Find the number to be multiplied
Let the required number be x.Then, `53x -35x` `= 1206` or `18x` `= 1206` or `x = 67` :. Required number `= 67`.
Question:In a callege, `1/5`th of the girls and `1/8` th of the boys took part in a social comp. What of the total number of students in the college took part in the camp.
Out of `5` girls `1` took in the camp. Out of `8` boys `1` took part in the camp. :. Out of `13` students ,`2` took part in the camp . :.`2/13` of the total strength took part in the camp .
Question:The highest score in an ining was `3/11` of the total and the next highest was `3/11` of the remainder . If the scores differed by `9`,find the total score.
Let, total scores be x ,The highest scores .`(3x)/(11)`. Remainder `= (x - (3x)/(11))` `= (8x)/(11)`. Next highest `= 3/11` of `(8x)/(11)` `= (24x)/(121)`. `:. (3x)/(11) - (24x)/(121) = 9` or `33x - 24x` `= 9 xx 121`. or `9x = 9 xx 121` or x `= 121` Hence total score`= 121`.
Question:In a km race, A beats B by 28 metres or 7 seconds. Find A'S time over the course.
Clearly, B covers 28 m in 7 seconds. :.B,s time over the course` = (7/28 xx 1000)` sec = 250 seconds. :. A's time over the course = (250 - 7) sec = 243 sec. = 4 min. 3 sec.
Question:A runs` 1 3/4` times as fast as B. If A gives B a start of 84 m,how far must the winning post be so that A and B might reach it at the same time ?
The ratio of the rates of A and B` = 7/4 : 1 = 7 : 4.` So, in a race of 7 m, A gains 3 m over B. :. 3m are gained by A in a race of 7m. :. 84 m are gained by A in a race of` (7/3 xx 84)` m = 196 m. :. Winning post must be 196 m away from the starting point.