Answer:
Number of Dolls = 28.
Number of Balls = 32.
Number of Cars = 20.
Step-by-step explanation:
Given the ratio of the number of dolls to the number of balls to the number of cars is 7 : 8 : 5.
Suppose the highest common factor of the three numbers be 'X'.
Then, Number of Dolls = 7x
Number of Balls = 8x
Number of Cars = 5x
Given the total number of dolls, balls, and cars is 80.
It means 7x + 8x + 5x = 80.
20x = 80
x = 80/20 = 4.
So, Number of Dolls = 7*4 = 28.
Number of Balls = 8*4 = 32.
Number of Cars = 5*4 = 20.
SOLUTION:
Case: Hypothesis testing
Step 1: Null and Alternative hypotheses

Step 2: T-test analysis

Step 3: t-test with the significance level

Step 4: Comparing

So tail to reject the null hypothesis. There is enough evidence at a 0.05 level of significance to claim that the mean spent is greater than P127.50.
Final answer:
Yes, there is evidence sufficient to conclude that the mean amount spent is greater than P127.50 per month at a 0.05 level of significance.
Answer:
Part 1: It is not a valid conclusion to say that track and field sports are more popular than soccer based on the survey. The survey was taken at a track and field event so the people that were surveyed are probably biased.
Part 2: A better way of determining which sport is more popular is by counting how many people show up to each event and comparing the results.
0.5 is a rational number.