What are the answers to the following ?'s thank you

  1. A bicycle has a diameter of 66 centimeters. How many times must the tire rotate to travel 1 kilometer?explain answer.

  2. Becky want to make a long distance call to her friend Sarah from a pay telephone.She has $5.00 in change.The call costs $0.90 for the first three minutes and $0.24 for each additional minute.How long can Becky talk to Sarah?
Hi Sarah,

Answering your first question will require a couple of intermediate steps.

  1. Using the fact that the tire has a diameter of 66 cm, calculate the circumference of the tire (because this is the part of the tire that tells you how far it travels when it rolls).

  2. You need to convert 1 kilometer into centimeters (easier to work with) or convert the circumference into kilometers (harder to work with) because we need to have the same units for both measurements.

  3. Divide the circumference of the tire into the distance it travels to get the number of times the tire rolls.

For your second question:

  1. Your first step is to subtract the initial $0.90 from the total available $5.00 and note that this gives Becky 3 minutes.

  2. To find the number of additional minutes you need to calculate how many times $0.24 goes into the balance remaining after step 1 (ignoring any fractional or part).

Hope this helps,
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