[SOLVED] (word problem) The price of a stock is linear with respect to time

Hello all,

I'm stuck with a problem here and don't really know where to start.

The price of a stock is linear with respect to time. If its price on Day 1 is 131 and its price on Day 3 is 135, what will its price be on Day 10?

If anyone can show me the formula and method of how to solve this I would appreciate it.

Thnkx

If the price is linear then on day x the price y is given by a formula y=mx+c where m and c are constants to be determined. You know that when x = 1, y=131 and when x=3, y=135. Substituting, 131=m+c and 135=3m+c. This is enough information to tell you m and c.