Question

22. In a packet of 500 screws, 80 screws are
defective. Find the probability that a screw
selected at random from the packet is non-
defective.​

Answer 1

Answer:

The probability is 21/25 or 0.85

Step-by-step explanation:

Total no. Of screws in the packet =500 screws

No. Of defective screws in the packet =80

No.of non defective screws = 500-80 = 420

Probability of selection of non defective screw = no. Of favourable outcomes /total no. Of outcomes

Probability = 420/500

=21/25=0.84

Answer 2

Answer:

$\underline{\tt Given :}$

In a packet of 500 screws, 80 screws are

defective.

$\underline{\tt Find :}$

Find the probability that a screw selected at random from the packet is non - defective.

$\underline{\tt Calculations :}$

$\underline{\tt According \ to \ the \ given question, \ as \ follows }$

500 screws = Total number of screws.

80 screws = Total number of defective screws.

$\underline{\tt Using \ Formula :}$

Total number if screws - Total number of defective screws.

$\sf \rightarrow 500 - 80 = 420$

Possibility of total number of non-defective screws = Number of postive outcome/ Overall outcomes.

$\rightarrow \sf \dfrac{No.of \ Positive \ Outcomes}{Overall \ Outcomes} \\ \\ \rightarrow \dfrac{420}{550} \\ \\ \rightarrow \sf 0.84$

Therefore, 0.84 is the probability that a screw selected at random from the packet is non - defective.