(1) THE SUM OF THE FIRST AND SECOND(B) 21TERMS IS ONE-HALF THE SUM OF THE2INCHESTHIRD AND FOURTH TERMS
10, x
1
15, . . .?
(1) The sum of the first and second
(B)
2
1
terms is one-half the sum of the
2
inches
third and fourth terms.
(C)
2
3
(2) The sum of the sixth and seventh
4
inches
terms is 43.
(D) 3 inches