The sum of the terms in a particular arithmetic sequence is 75.
If you only sum EVERY OTHER term (starting at and ending on the same terms as before), you get 39.
What is the sum of EVERY THIRD term (again, starting at and ending on the same terms)?
#iTeachMath
If you only sum EVERY OTHER term (starting at and ending on the same terms as before), you get 39.
What is the sum of EVERY THIRD term (again, starting at and ending on the same terms)?
#iTeachMath
Comments
Nice one!
0,1,2,3,4,5 (needs 6 terms bc mult of 2 and 3) makes 15 so add 10 to each;
11+13+15 = 39 as desired 😆
answer is 13+15=28
brain use: low
luck: high lmao