Answer:
Sum = -1930
Step-by-step explanation:
Sum of an arithmetic series;
;Sum = n/2[ 2a1 + ( n - 1 )d]
Then substitute into the equation above
; Sum = 20/2 [ 2(-68) + (19)-3 ]
; Sum = 10 [ -136 - 57 ]
Therefore the sum of the arithmetic series
is....; -1930
