Question:
If a sample of 2 hammer is selected
(a) find the probability that all in the sample are defective.
(b) find the probability that none in the sample are defective.
Answer:
a 
b 
Step-by-step explanation:
Given
--- hammers
--- selection
This will be treated as selection without replacement. So, 1 will be subtracted from subsequent probabilities
Solving (a): Probability that both selection are defective.
For two selections, the probability that all are defective is:




Solving (b): Probability that none are defective.
The probability that a selection is not defective is:

For two selections, the probability that all are not defective is:




Answer:
S=157
Step-by-step explanation:
an= a1+(n-1)d
a2=80+(2-1)(-3)
a2=80-3
a2=77
Sn=(a1+an)*n/2
S2=(80+a2)*2/2
S2=(80+77)*1
S2=157
Answer:
23+7-2x=8x
We simplify the equation to the form, which is simple to understand
23+7-2x=8x
We move all terms containing x to the left and all other terms to the right.
-2x-8x=-23-7
We simplify left and right side of the equation.
-10x=-30
We divide both sides of the equation by -10 to get x.
x=3
Step-by-step explanation:
Answer: original angle = 75°
Its supplement 105°
Its complement = 15°
Step-by-step explanation:
We know that,
- Sum of supplementary angles is 180 degrees.
- Sum of complementary angles is 90 degrees.
Let x be the original angle , then its supplement = 180° - x
its complement = 90° - x
As per given,
180° - x = 7(90° - x)
⇒ 180° - x = 630° - 7x
⇒ 7x- x = 630° -180°
⇒ 6 x = 450°
⇒ x = 75° [divide both sides by 6]
So, original angle = 75°
Its supplement = 180° - 75° = 105°
Its complement = 90° -75° = 15°
Hence, original angle = 75°
Its supplement 105°
Its complement = 15°
Answer:
5.6
Step-by-step explanation:
by dividing