Step-by-step explanation:
look at the picture !
she has to paint actually 6 rectangles :
the 3 tops of the 3 stairs.
and the 3 vertical front boards (the front of each step of the stairs).
what is the area of these rectangles ? summing up all 6 - that is the surface area to be painted.
each top rectangle is clearly
82×19 (19 cm deep) = 1558 cm²
each front board is
82×12 (12 cm high) = 984 cm²
so, in total we have
3×1558 + 3×984 = 4674 + 2952 = 7626 cm²
as surface area to be painted.
Answer:
7.2 years
Step-by-step explanation:

where f(t) is the length and t is the number of years old
given the Mike measures 148 cm, we need to find out the age
So we plug in 148 for f(t) and solve for t

divide both sides by 200

Now subtract 1 from both sides

Divide both sides by -0.956

Now take ln on both sides



divide both sides by -0.18
t=7.2
So 7.2 years
Answer:
Mean = 21.3
Standard Deviation = 2.48
Step-by-step explanation:
We are given the following in the question:
p = 71% = 0.71
Sample size, n = 30
We have to find the mean and the standard deviation of those that wear glasses.

Thus, the mean of those who wear glasses is 21.3

Thus, the standard deviation of those who wear glasses is 2.48