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%.
Answer:
Step-by-step explanation:
sin x=a+b
cos x=a-b
sin²x+cos²x=(a+b)²+(a-b)²=2a²+2b²
or 2a²+2b²=1
a²+b²=1/2 which is constant for all values of x
(ii)

3z + 6
3z and 6 has greatest common factor, that is 3. Divide 3z and 6 by the greatest common factor (3).
3z ÷ 3 = z
6 ÷ 3 = 2
So, we could work on the expression as following.
3z + 6
= 3 × z + 3 × 2
From the expression above, we should separate 3 from z and 2 by a parenthesis to make distributive property.
3 × z + 3 × 2
= 3(z + 2)
SUMMARY
3z + 6
= 3 × z + 3 × 2
= 3(z + 2)
Answer:
Step-by-step explanation:
<u>The ratio is given:</u>
<u>Let each equal part be x, then we have:</u>
- b - r = 6
- 9x - 6x = 6
- 3x = 6
- x = 2
<u>Total number of counters:</u>
- 2(9 + 6 + 3) = 2(18) = 36