ratio of voljumes = 3^3 : 4^3 or 27:64
small/large = 27 / 64
vol of smaller = 27 * 320 / 64
=135
180-2(55)-x=0
180-110-x=0
70-x=0
-x=-70
x=70°
Answer:
11.95 dollars
Step-by-step explanation:
Cost of one LED bulb = 6.95 dollars
Cost of changing one bulb = 3 dollars
Life of each bulb = 5 years.
In 10 years, only one time after 5 years the bulbs would have been changed
Hence cost of 100 lamps = 695 and
cost of changing once = 500
Total cost = 1195 dollars for 11 years
Divide this by 10 years to get average cost per year
Cost of 100 lamps per year = 1195/100 = 11.95 dollars