Question

if it cost $25 to make 2 calculators, $59 to make 4 calculators, and $305 to make 10 calculators then how much does it cost to make 1 calculator​

Answer 1

Answer:

$a + d = 25 \\ a + 3d = 59 \\ a + 9d = 305$

$d = \frac{59 - 25}{2} = \frac{34}{2} = 17$

So,

$a = 8$