Answer:
Step-by-step explanation:
Note that 20 (an approximation for 205) less 4 (an approx. for 431) comes out to 16.
This tells us that the proper placement of the decimals is
20.50
- 4.31
----------
and this comes out to 16.19.
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
Hello what numbers of fractions do u want listed