15 is 60 percent of 25. 15x100/60 and it should be 25.
Answer:

Step-by-step explanation:
From the Venn diagram, n(AUB)=31
The given probabilities in the option are calculated below:

The only correct option is the probability of B which is 
2 times (9+7) is correct.
9 + 7 = 16.
16 multiplied by 2 is 32.
Answer:
n=6
Step-by-step explanation:
4n + 1= 25
Move constant to the right
4n=25-1
Calculate
4n=25-1
Then divide on both sides