Answer:
0.5
Step-by-step explanation:
Solution:-
- The sample mean before treatment, μ1 = 46
- The sample mean after treatment, μ2 = 48
- The sample standard deviation σ = √16 = 4
- For the independent samples T-test, Cohen's d is determined by calculating the mean difference between your two groups, and then dividing the result by the pooled standard deviation.
Cohen's d = 
- Where, the pooled standard deviation (sd_pooled) is calculated using the formula:

- Assuming that population standard deviation and sample standard deviation are same:
SD_1 = SD_2 = σ = 4
- Then,

- The cohen's d can now be evaliated:
Cohen's d = 
Set up a proportion: 25/100 = 50/n where n = # of teens surveyed
Simplify fraction: 1/4 = 50/n
Cross multiply: n = 200
So 200 teens were surveyed.
Find his rate:
120 / 15 = $8 per hour
Multiply the rate by hours:
$8 x 20 hours = $160
He will earn $160
Its a monomial and it has 4 terms