The cost of other seats £40 and £24.
A ratio is an ordered pair of numbers a and b, written a / b where b does not equal 0.
Given ratio: A: B : C = 5 : 3 :2
let the common ratio be 'x'.
Grade A cost = 5x
Grade B cost = 3x
Grade C cost = 2x
cheapest seats the concert £16
So,
2x=16
x=8
Now, Grade A cost = 5x = 5*8 = £40
Grade B cost = 3x= 3*8 = £24.
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