First of all that is NOT math and second of al that is not english
No the answer is 5x because simply then,add x
Since you said the height of your chair and you desk, chair would go first when subtracting.
C= chair
c - 29.75 = -10.25
+ 29.75 = + 29.75
c= 19.5
So, you chair is 19.5 (19 1/2) inches tall.
In Binomial distribution, the expected value or mean is given by,
E(X) = np
where, p = probability of success and n=number of sample size.
E(X) = 100×0.4 = 40