Answer: for the first it is not direct varition while for the second one it i s
Step-by-step explanation:
Answer:
28.26
Step-by-step explanation:
π r² = A
A = (3.14) (3²)
A = 3.14 · 9 = 28.26
x + y = 53
x -y = 9 Adding both equations
2x = 62
x = 31 y = 22
Answer: 0.951%
Explanation:Note that in the problem, the scenario is either the adult is using or not using smartphones. So, we have a yes or no scenario involved with the random variable, which is the number of adults using smartphones. Thus, the number of adults using smartphones follows the binomial distribution.
Let x be the number of adults using smartphones and n be the number of randomly selected adults. In Binomial distribution, the probability that there are k adults using smartphones is given by

Where p = probability that an adult is using smartphones = 54% (since 54% of adults are using smartphones).
Since n = 12 and k = 3, the probability that fewer than 3 are using smartphones is given by

Therefore, the probability that there are fewer than 3 adults are using smartphone is 0.00951 or
0.951%.
There are 25 $10 bills and 11 $20 bills.
Step-by-step explanation:
Given,
Worth of proceeds from garage = $470
Let,
x be the number of $10 bills
y be the number of $20 bills.
According to given situation;
10x+20y=470 Eqn 1
x = y+14 Eqn 2
Putting value of x from Eqn 2 in Eqn 1

Dividing both sides by 30

Putting y=11 in Eqn 2

There are 25 $10 bills and 11 $20 bills.
Keywords: linear equation, substitution method
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