Question

To lose one pound of fat, a 200-pound person must burn 3,500 calories. If that person burns 180 calories by walking for 30 minutes, how many hours and minutes does the person have to walk to lose two pounds? Round your answer to the nearest minute. A. 53 hours 38 minutes B. 38 hours 53 minutes C. 19 hours 27 minutes D. 39 hours

Answer 1

It would be c because 3500*2 is 7000. So 7000 / 180 is 38.8. So he has to walk 30 minutes, 38 times, so 30 time 38 minutes will get you 1166 mins and divided by 60 mins in an hour will get you 19.4 hours which is closest to C.

Answer 2

For this case we have:

You lose 180 calories by walking 30min, that is:

180cal ---------> 30min

If to lose 1 pound of fat, the person should burn 3500 calories, to lose 2 pounds should burn twice the calories, that is, 7000 calories.

You want to know how long it takes to burn 7000 calories, knowing that they burn 180 in 30min. So:

180cal ---------> 30min

7000cal -------> x

Where x represents the time that must be used to burn the 7000 calories.

Resolving we have:

`x = ((7000cal * 30min))/(180cal)\\`

`x = 1166.7min\\`

If 1h has 60min, then:

`x = ( (1166.7min * 1h))/(60min)\\`

`x = 19.44h\\\\x = (19h + 0.44h)\\`

0.44h equals
`0.44 * 60min = 26.4min\\`

Thus, for the person to burn 7000 calories and lose 2 pounds, he must walk
`x = 19h + 26.4min`.

Answer:

`x = 19h + 26.4min\\`

Option C.