Question

The mean attendance of a class from Monday to Saturday was 34. If the mean attendance on Monday, Tuesday, Wednesday and Thursday was 33 and that on Thursday, Friday and Saturday was 35, then find the attendance on Thursday.

Answer 1

Step-by-step explanation:

Given, mean attendance of a class from Monday to Saturday = 34

=> (Mon + Tue + Wed + Thu + Fri + Sat)/6 = 34

=> Mon + Tue + Wed + Thu + Fri + Sat = 34 * 6

=> Mon + Tue + Wed + Thu + Fri + Sat = 204   .............1

Again, mean attendance on Monday, tuesday, wednesday and thursday = 33

=> (Mon + Tue + Wed + Thu)/4 = 33

=> Mon + Tue + Wed + Thu = 33 * 4

=> Mon + Tue + Wed + Thu = 132   .............2

and mean attendance on thursday, friday and saturday = 35

=> (Thu + Fri + Sat)/3 = 35

=> Thu + Fri + Sat = 35 * 3

=> Thu + Fri + Sat = 105   .............3

Add equation 2 and 3, we get

=> Mon + Tue + Wed + 2Thu + Fri + Sat = 132 + 105

=> Mon + Tue + Wed + 2Thu + Fri + Sat = 237  

=> (Mon + Tue + Wed + Thu + Fri + Sat) + Thu = 237

=> 204 + Thu = 237                    [From equation 1]

=> Thu = 237 - 204

=> Thu = 33

So, the attendance on thursday was 33