Answer:
the answer is true.. I think
If the 5 scores have a mean of 8, then their total sum would be 8*5 = 40
Now if one score if added (let's call this score x), there are 6 scores and the mean changes to 9, thus:
(40 + x)/6 = 9
40 + x = 54
x = 14
Answer:
m = 48
Step-by-step explanation:
6=m/8
Multiply each side by 8
6*8 = m/8 *8
48 = m
Answer:
£191.36
Step-by-step explanation:
Sum the parts of the ratio, 1 + 4 = 5 parts
Divide 320 by 5 to find the value of one part of the ratio.
320 ÷ 5 = 64 ← value of 1 part of the ratio , thus
4 parts = 4 × 64 = 256
Thus he bought 64 first class and 256 second class.
Cost = (64 × £0.67) + (256 × £0.58)
= £42.88 + 148.48
= £191.36