Question

Form a sequence that has two arithmetic means between -1 and 59.

a.
-1, 29, 29, 59
c.
19, -1, 59, 39
b.
-1, 19, 39, 59
d.
-1, 14, 29, 44, 59

Answer 1

two arithmetic means between -1 and 59.
b.-1, 19, 39, 59

Answer 2

The formula for solving the problem is as follow:
an = a1 + (n - 1)d
Where:
n = number of figure in the sequence = 4
d = difference between successive number =?
a1 = -1
a4 = 59
Insert the given values into the formula,
59 = -1 + (4 - 1)d
59 = -1 + 3d
59 + 1 = 3d
60 = 3d
d = 60/3 = 20
Therefore, d = 20. This implies that, there is a difference of 20 between successive numbers.
The number sequence is as follow:
-1, 19, 39, 59.