Answer: Jane needs to reduce the price by 20%
Step-by-step explanation: The first thing to note is the original price of the cereal and that is given as £3 for every 160 grams.
The change proposed by Tim is as follows;
Put 25% more cereal in the box (and do not change the price). That means 160 g plus 25%. Mathematically, this can be expressed as;
New weight = 160 + (160 * 25%)
New weight = 160 + (160 * 0.25)
New weight = 160 + 40
New weight = 200
Hence, Tim's idea would result in a cereal box with 200 grams that still cost £3. At this rate, each gram would cost
1 gram = Price / Total grams
1 gram = 3/200
1 gram = 0.015
However, Jane has proposed that the amount of cereal in the box should not be changed, which means the box of cereals should remain 160 grams. The price should be reduced to give the same value as Tim's idea. This means 160 g of cereals should now sell for £0.015 per gram. That would bring the price of 160 g to,
1 gram = 0.015
160 grams = 0.015 * 160
160 grams = 2.4
With Jane's proposal, a 160 g box of cereal should now be sold at £2.4 each. That is a reduction of £0.6
Therefore, the percentage reduction can be calculated as follows;
% decrease = (0.6/3) * 100
% decrease = (1/5) * 100
% decrease = 20
From the results above, Jane should reduce the price (£3 per 160 g) by 20%.
