Answer:
59.25 currency ; No. of cans rounded to next whole number
Step-by-step explanation:
Draw a perpendicular line frrom the 12m. line onto the 20m. line. We get a rectangle on the left and a right-triangle on the right.
Using Pythagorous theorem,
Fence = m = 15 m
So, area of the lawn = ( 1/2 ) * ( 12 + 20 ) * 16 sqm = 240 sqm
So, number of cans needed = 240/100 = 2.4 ≈ 3 [Cause cans can't be partially bought ]
Total cost = 3 * 19.75 currency = 59.25 currency
( However, if cans can be partially bought, then total cost = 47.4 currency )