Sum = n/2[2a + (n - 1)d] where a = first term, n = number of terms and d = common difference
(a) 30/2(2 x 5 + (30 - 1) x d) = 1455
10 + 29d = 1455 / 15
29d = 97 - 10
d = 87 / 29 = 3
(b) 7/2(2 x 9 + (7 - 1)d) = 0
18 + 6d = 0
6d = -18
d = -3
Answer:
70 cm^2
Step-by-step explanation:
The area of square is 5×10=50 plus the square of triangle, high of triangle is 18-10=8 and base of triangle is 5 because it common base with square, so the square of triangle is 1/2(8)(5)=20
The total area is 50+20=70 cm^2
Answer:
SE = 0.025
Step-by-step explanation:
We are given;
Sample mean; x¯ = 14.52
Sample standard deviation; s = 0.075
Sample size; n = 9
Now,formula for standard error of sample mean is;
SE = s/√n
SE = 0.075/√9
SE = 0.075/3
SE = 0.025
