Step-by-step explanation:
the probability of A working is 60% or 0.6, so the probability it does not work is 40% or 0.4.
the probability of B working is 90% or 0.9, so the probability it does not work is 10% or 0.1.
plan 1
it is the probabilty that either A works, or (if it is not working) B works.
0.6 + 0.4×0.9 = 0.6 + 0.36 = 0.96
plan 2
either B works, or (if it is not working) A works
0.9 + 0.1×0.6 = 0.9 + 0.06 = 0.96
both plans have the same success probability.
The ratio of boys to girls is 3/5.
Answer:
a. 2.5
b. 2.333
c. 2.85
Step-by-step explanation:
A) 1. subtract -x on both sides 2. to get 3x-1/2=7
3. Add 1/2 on both sides 4. to get 3x=7.5
5. divide 3 on both sides 6. To get... x=2.5
B)1. Same process. 2. x+2=13/3
3. x=13/3-2 4. x= 2.33(repeating)
C) 1. same process. 2. 2x-x/3=3+7/4
3. 2x-x/3=4.75 4. Isolate -x/3
5.-x/3=4.75-2x 6. multiply both sides by 3
7. -x=14.25-6x 8. 5x=14.25
9. x= 2.85
* remember to distribute the 3 to each variable.
Answer:
(D) Although cause-and-effect cannot be established, there is an association between stress and the presence of heart arrhythmias for the population of all women aged 30 to 50.
Step-by-step explanation: