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vesna_86 [32]
3 years ago
8

Five bulbs of which three are defective are to be tried in two bulb points in a dark room

Mathematics
1 answer:
iogann1982 [59]3 years ago
8 0

Answer:

D 7

Step-by-step explanation:

Total no. of bulb= 5

no. of defected bulb= 3

no. of not defected bulb=2

Total no. of bulb combination = 5C2

=5!/2!(5-2)!

= 5!/2!3!

= 5×4×3×2×1/2×1×3×2×1

=120/12

=10

( since a room can be lighted with one bulb also)

total no. of bulb combination when room shall not light = 3C2

3!/2!(3-2)!

= 3!/2! 1!

= 3×2×1/2×1×1

= 6/2

=3

Now,

Total no. of trial when room shall light

=10-3

=7

Hence, number of trial when the room shall be lighted is 7 which is option d

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The amount of jobs from fitting industry shall decline in 5.5 percent from 2015 to 2025.

Step-by-step explanation:

Due to the assumption of a yearly average rate, a linear function model shall be used. The expected amount of jobs (n) after a certain amount of years (t) is given by the following formula:

n = n_{o} + \frac{\Delta n}{\Delta t}\cdot t

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The amount of jobs from fitting industry shall decline in 5.5 percent from 2015 to 2025.

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