## katiebugg 2 years ago a1 = 5, an = 3, n = 20

1. amistre64

baking cupcakes are you?

2. katiebugg

no

3. katiebugg

find the sum of the arithmetic sequence having the data given.

4. amistre64

oh, thats doable then, use the formula: $\frac n2(a1+an)$

5. katiebugg

thanks!