Answer:
Step-by-step explanation:
a^2 - 5bc - 1
a = 7
b = 3
c = 2
7^2 - 5*3*2 - 1
49 - 30 - 1
18
Given that 4000 items are checked in one month, let the number of detective items be represented as y.
Quality control finds on average that 0.026% of the items in the factory are detective. This implies that

When 4000 items are checked, we have the number of detective items to be evaluated as

Hence, the number of detective items is 1.04.
3926/13 =302 but I'm not 100% sure where you went wrong do you have any work?
Answer:
a. 254.34, b. 56.52
Step-by-step explanation:
a. A = πr^2,
A = 3.14(9^2)
A = 3.14*81
A = 254.34
b. C = πd
C = 18*3.14
C = 56.52
54 rounded to the nearest 10 would be 50 because 54 is closer to 50 than 60.
So, the answer is 50.
Hope it helps