Question

Find the number of terms of AP -10,-6.-2, 6.... sunup to 1140?

Answer 1

Answer:

Here, a=-10

d=-6-(-10) = -6+10 =4

an=1140

an=a+(n-1) d

1140= -10+(n-1) 4

1140= -10+4n-4

1140= -14+4n

1140+14=4n

1154=4n

n=1154/4n=577/2