For each of the following situations, is the percent of change between 20% and 30%?

a) A $12 cost increases to $15
b) A boys height increases from 52 inches to 61 inches
c) The temperature falls from 3 degrees to 2 degrees.

  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%

A percentage change can be calculated from ...

  ((new value)/(old value) -1) × 100%

answer: given that the roller coaster can accommodate 1600 riders per hour, thus the roller coaster can accomodate 1600 / 60 = 26.67 riders per minute.

given that there are 345 people in the line, the number of minutes it will take for the 345 persons to get into the roller coaster is given by 345 / 26.67 = 12.94 minutes.

therefore, it will take you 12.94 minutes to get to the front of the line.

step-by-step explanation:

for the points! : )