Thursday, July 31, 2008

assignment for 4B (updated with answers)

1. The sides of a rectangle are given as x cm and y cm, where

17.5 ≤ x ≤ 18.5 and 11 ≤ y ≤ 12.

Calculate

(i) The smallest possible value of the perimeter of the rectangle,

(ii) The largest possible value of the area of the rectangle

2. A restaurant owner pays a waiter an amount of $A per week. The amount is made up of a basic wage of $ 60 plus 11 cents for each of the n customers he serves.

The formula connecting A and n in this case is

A = 60 + 11n/100

(i) Calculate the amount of money the waiter received in a week when he served 240 customers. [ans : $86.40]

(ii) At the end of another week, the waiter received $ 115. How many customers did he serve? [ans : 500]

(iii) The owner of the restaurant decides to decrease the waiter’s basic wage to $ 45 but to increase the pay per customers to 17 cents. Write down the new formula connecting A and n. [ans : A = 45 + 17n/100]

(iv) Find the number of customers the waiter would have to serve in a week for him to receive the same amount of money whichever formula is used. [ans = 250]