Question

find the sum of all the multiples of 3 laying between 250 and 1000​

Answer 1

Step-by-step explanation:

first multiple of 3=252

sec multiple of 3=255

last multiple of 3=999

now , d=3

therefore sum of the no.s=[2a+(n-1)d]n/2

do it urself mate.hope this helps.and to find n

simply use the formula

nth term=a+(n-1)d

here nth term is 999.we know d.we know a .find out n.