Answer:
The desired single multiplier is 1.26.
Step-by-step explanation:
A 5% increase results in the original amount PLUS 5% of the original amount:
1.05(original amount)
If a 20% increase follows, we must multiply the above 1.05(original amount) by 1.20:
1.20(1.05)(original amount), or (after multiplying), 1.26.
The desired single multiplier is 1.26.
