Solution :
Let x be student will be left handed
P = 0.09
Using the normal approximation to binomial distribution,
a). n = 108,
μ = np = 9.72


= 2.9741
Required probability,
P(x=8) = P(7.5 < x < 8.5)


Using z table,
= P(z<-0.41)-P(z<-0.75)
= 0.3409-0.2266
= 0.1143
b). P(x=12) = P(11.5 < x < 12.5)


Using z table,
= P(z< 0.94)-P(z< 0.60)
= 0.8294 - 0.7257
= 0.1006
Givens
======
b = 13
h = 9
Area = b*h
Area = 13*9 = 117 square in
Trapezoid
========
Givens
b1=9
b2 = 15
h = 14
Area = (b1 + b2)*h/2
Area = (9 + 15)* 14/2
Area = 24 * 14 / 2
Area = 336/2
Area = 168 square inches.
Rhombus
=======
I can't see the second number I'll make one up. Redo the questioin and put a the number in
Area = 1/2 * d1 * d2
d1 = 18
d2 = 12 substitute what it really says here.
Area = 1/2 * 18 * 12
Area = 108