Answer:
(i)

(ii)

(iii) $36.5
Explanation:
Given that:
1. Total Number of fruits = 80
2. Number of mangoes = x
3. Both mangoes and oranges are there in the basket.
Solution (i):
Only mangoes and oranges are there in the basket and the basket is full.
so, Number of mangoes + Number of oranges = Total number of fruits
x + Number of oranges = 80
Number of oranges =

Solution (ii):
Given:
Cost of an orange = 50 cents = $0.50
Cost of a mango = 40 cents = $0.40
Cost for x mangoes =

Cost for (
) oranges =


Solution (iii):
Put value of x = 35 in S(x)

Hence, answers are:
(i)

(ii)

(iii) $36.5