Mike enters the Vermilion game with a batting average of .274. After going 3-for-4 in the game, his batting average jumps up to .289. How many hits did he have for the season before the Vermilion game began?
Solution
We recall that a batting average of .274 means that bh=0.274, which is almost certainly rounded from some long decimal.
So bh=0.274, and b+4h+3=0.289 (again, rounded).
So we wheel up the algebra machine:
h=0.274b and h+3=0.289(b+4)=0.289b+1.156.
0.274b+3=0.289b+1.156→0.015b=1.844 (=3−1.156)
→b=0.0151.844=122.933... Let's assume 123.
Then h=0.274x123=33.702. Let's assume 34.
Checking, 12334=0.27642... So we've got rounding issues.
0.276 is a bit too big. Should we try b=124 12434=0.27419... That's pretty good.
And 124+434+3=0.28906... Also pretty good.
If you start over using these 5-place decimals, you'll get 34 and 124 almost exactly.