Hi KateM let me try to provide some explanation on this question.
This is a grouping concept question.
We are able to find the cost of the items individually based on the workings and hence answer part a) as well. It is quite straight forward. The answer is $117.
In part b), we make use of grouping concept.
The ratio of tennis rackets sold to badminton rackets sold is 2 : 3. That means that we are actually able to group 2 tennis rackets with 3 badminton rackets, and there will not be any remaining rackets that doesn’t belong to any group. This is how the grouping concept is related to any given ratio.
Since we know that one group consists of 2 tennis rackets and 3 badminton rackets, we find out that the amount collected in 1 group, would be $897.
Since we also know that Mrs Sim has collected $17043, we divide it by $897 to get 19.
19 represents the number of groups we are able to get.
Remember, there are 3 badminton rackets per group, so 19 x 3 = 57.
We have 57 badminton rackets.
Hope this solution provided above helps!
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