Answer:
$1.25 per minute
reason:
to find the cost per minute, you divide the money by the number of minutes
for this problem, divide 50 by 40 to get 1.25
We use the identity sin (A - B) = sin A cos B - cos B sin A
so the above = sin (11pi/12 - pi/6) = sin 3pi/4 = 1 / sqrt2 answer
Let 't' represent the time of the walk in minutes.
5.1*t = 220
t = 43.14 min
The person needs to walk at least 43.14 minutes to but at least 220 calories.
