Answer:
-12.5%
Step-by-step explanation:
A percentage change is computed using ...
percent change = ((new amount) -(original amount))/(original amount) × 100%
We want to find the percentage change from 4.8 m, so we have ...
percent change = (4.2 -4.8)/4.8 × 100% = -.6/4.8×100% = -12.5%
The carpenter made the track 12.5% too short.
