Higher June 2018 Paper 2 Q7
7 The students in Class A and in Class B take the same examination.
There are 28 students in Class A and 32 students in Class B.
The mean score for all the students in both classes is 72.6
The mean score for the students in Class A is 75
(a) Work out the mean score for the students in Class B. (4)
The lowest score in Class A is 39
The range of scores for Class A is 57
The lowest score in Class B is 33
The range of scores for Class B is 60
(b) Find the range of scores for all the students in both classes. (3)
| Scheme | Marks |
|---|---|
| (28 + 32) × 72.6 (= 4356) or 28 × 75 (= 2100) | M1 |
| (28 + 32) × 72.6 − 28 × 75 (= 2256) | M1 |
| \(\dfrac{(28 + 32) \times 72.6 - 28 \times 75}{32}\) (= “2256” ÷ 32) | M1 |
| 70.5 | A1 |
| (4) |
Notes
M1: Expression for total of both classes together or total of class A
M1: Expression for total of class B.
M1: Correct calculation for mean of class B
| Scheme | Marks |
|---|---|
| Highest in A = 39 + 57 (= 96) Highest in B = 33 + 60 (= 93) | M1 |
| (39 + 57) − 33 | M1 |
| 63 | A1 |
| (3) | |
| (7 marks) |
Notes
M1: for 39 + 57 (=96) or 33 + 60 (=93)
M1: or for 33 – “96” or 33 to “96” oe