Study the following table and answer the question:
Number of Students Appeared (A) and Passed (P) in an annual examination from four schools Q, R, S & T in five years (2014 to 2018)
| School/Year | Q | R | S | T | ||||
| A | P | A | P | A | P | A | P | |
| 2014 | 320 | 240 | 400 | 340 | 420 | 273 | 250 | 225 |
| 2015 | 400 | 320 | 380 | 285 | 350 | 280 | 300 | 228 |
| 2016 | 440 | 286 | 360 | 288 | 330 | 264 | 320 | 256 |
| 2017 | 350 | 252 | 420 | 294 | 380 | 247 | 350 | 315 |
| 2018 | 375 | 320 | 450 | 405 | 400 | 344 | 375 | 300 |
The difference between the average number of students who passed from school R in 2015 to 2017 and the number of students who passed from school Q in 2015 is x. the value of x lies between :
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 30 and 35
The average number of students who passed from school R in 2015 to 2017 = (285 + 294)/2 = 289.5
The average number of students who passed from school Q in 2015 = 320
Required difference = 320 - 289.5 = 30.5.