Eighty percent of the lights at hotel california are on at 8 p. m. a certain evening. however, forty percent of the lights that are supposed to be off are actually on and ten percent of the lights that are supposed to be on are actually off. what percent of the lights that are on are supposed to be off?
a. 22(2/9)%b. 16(2/3)%c. 11(1/9)%d. 10%e. 5%

option D

Step-by-step explanation:

Assume number of bulb in the hostel be 100

number of bulb on at 8 p.m.

           = 80 % of total bulb

           = 0.8 x 100 = 80 bulb

Let L be the number of light on and 100 - L be the light that are off

now,

Light on = 40 % of (100 - L) + 90 % of L

80 = 40 - 0.4 L + 0.9 L

40 = 0.5 L

 L = 80 bulb

number of bulbs which were off = 100-80 = 20 bulb

number of bulbs that are on are supposed to be off =  40 % of 20

                = 0.4 x 20 = 8 bulbs

percentage =

                   = 10 %

Hence, the correct answer is option D

6,250

step-by-step explanation:

to get the area, multiply 360 by 160.(57,600)

to find out how many bags of fertilizer it will take, first figure out how many square feet one bag can hold. divide 1000 by 8(125) to get the unit rate(how many square feet one pound of fertilizer can hold)and multiply it by 50(6250). if i haven't made a mistake, that is the answer.