Answer:
less value
Step-by-step explanation:
To deterimine if value was improved or not, we need to compare the price reduction to the size reduction.
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The reduction in price is ...
((new value)/(old value) -1) × 100%
= (42/50 -1) × 100% = -16%
The size reduction of 20% is more than the price reduction of 16%, so the chocolate bar is <em>less value</em>.
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<em>Additional comment</em>
Compared to the original value, the new price to chocolate ratio is ...
0.84/0.80 = 1.05
Effectively, the price was raised by 5%.