SOLUTION
From the sequence give
–3, 1, 5, 9, . . .
The first term, a = -3
The common difference, d = 4 (gotten by adding 4 to the next term).
The number of terms required n = 6.
Formula for sum of an arithmetic sequence is given by
Substituting these values into the equation above we have
Hence, the answer is 42, option B
Add all the pieces:
6 + 4 + 3 + 5 = 18
In 18 pieces, there are 4 raisins, so in 9 pieces, there are 2 raisins.
The length is 25.
Do 7 × 2 = 14, then 64 - 14 = 50. Then do 50 ÷ 2 to give you 25.
First, write put the information into an equation
2*(x+9) = 3*(x-7)
distribute the 2 and 3
2x + 18 = 3x - 21
Combine like terms (Xs and munbers) (in this case, it's easier to add 15 to both sides and subtract 2x from both sides so both sides end up being positive)
33 = x
x=33