Susan has a goal to complete a triathlon. The race consist of a 0.93 mile swim, a 24.8 mile bike ride and a 6.2 mile run. In training, Susan

Question

Susan has a goal to complete a triathlon. The race consist of a 0.93 mile swim, a 24.8 mile bike ride and a 6.2 mile run. In training, Susan can swim at an average pace of 1.2mph. She rides her bike at an average of 18.8 mph and runs at 5.1 mph. Estimate how long it will take her to complete the triathlon.

Answer 1

Kaila, d = rt, so t = d/r

 

.93/1.2 + 24.8/18.8 + 6.2/5.1 = 3.3 hours = 3 hours, 18 minutes.

Answer 2

We can use the relationship distance = rate x time to determine this.

For each leg of the triathlon, we know the distance and the rate. Let's call them d and r, respectively. We need to find the time, which we will call t. 

 

d = r x t    or 

t = d/r

 

Now, let's look at each leg of the race.

 

I will re-write the decimals as fractions to simplify the calculations.

 

For swimming, the distance is 0.93 or 93/100 and the rate is 1.2 or 12/10. Using our formula, we have:

 

93/100 divided by 12/10, which is the same as

93/100 * 10/12

= 93/120 = 31/40 = time to swim 

 

For biking we have a distance of 24.8 or 248/10 and a rate of 18.8 or 188/10. Using the same equation, we have:

 

248/10 divided by 188/10 or

248/10 * 10/188 = 248/188 = 62/47 = time to bike

 

Finally, for the run the distance is 6.2 = 62/10 and the rate is 5.1 or 51/10. Plugging this into the formula gives:

 

62/10 divided by 51/10 or 

62/10 * 10/51 = 62/51 = time to run

 

To determine how long it will take to complete the triathlon, we total the sum of the times to complete each of the three legs of the triathlon (swimming, biking, running)

 

= 31/40 + 62/47 + 62/51

 

To solve this, find a common denominator, or you can convert them back to decimals and express the time as a decimal.