Answer:
11%
Step-by-step explanation:
<em>Percentage increase = (New average- previous average)/previous average x 100</em>
<em>New average: 1554</em>
<em>Previous average: 1400</em>
Percentage increase = (1554-1400)/1400 x 100
Percentage increase = 154/1400 x 100
Percentage increase = 0.11 x 100
Percentage increase = 11%
Therefore, the average increased by 11%.
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