Question

In one problem, he gave her a store receipt that listed 72 identical items, each the

same price, for a total cost of

$ * 67.9*

Bryn's Grandpa covered the first and last digits of the total price on the receipt

with stars.

Determine the values of the digits that Bryn's Grandpa covered.

Answer 1

The first covered digit = x = 3

The last covered digit = y = 2

The total price on the receipt = $367.92

Explanation:

Given data:

total cost = $ * 67.9*

First we check for the multiples of 72

9 × 8 = 72

Let

the first covered digit be denoted by x

the last covered digit be denoted by y

Solution

First we find the last covered digit

If a number should be divisible by 8,

It must be a multiple of 8

From the given price:

The last 3 digits = 79*

number in multiples of 8

7.9* = 7.20 + 0.64+ 0.08

7.9* = 7.92

Therefore, the last two digit is 2.

Next We find the first covered digit.

If a number is divisible by 9, it is a multiple of 9

The first digit = x would be determined as:

= x + 6 + 7 + 9 + 2

= x + 24

= x + 24

multiple of 9 nearer to 24 = 27

27 = x + 24

x = 27 - 24

x = 3.