
Answer:
 a) yes
 b) no
 c) no
Step-by-step explanation:
a) The percentage change from 12 to 15 is ...
  (15/12 -1)·100% = 1/4·100% = 25% . . . . between 20% and 30%
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b) The height increased by 61-52 = 9 inches. 20% of 52 inches is 10.4 inches, so the increase was less than 20%.
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c) The increase was negative, so was not between two positive values.
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In summary ...
 a) yes, 25% is between 20% and 30%
 b) no, 17.3% is NOT between 20% and 30%
 c) no, -33.3% is NOT between 20% and 30%
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A percentage change can be calculated from ...
 ((new value)/(old value) -1) × 100%