80% of 200 multiplied by 60% of 300 gives :
29000
28000
28800
30800
80% of 200 = 80100×200 = 160
60% of 300 = 60100×300 = 180
160 × 180 = 28800
Life (in Hrs.)
0-20
20-40
40-60
60-80
80-100
100-120
No. of electric bulbs
31
36
38
42
82
71