Answer:
The base amount is $48.
Step-by-step explanation:
We are given the following in he question:
Amount after increase = $55.20
Rate of increase = 15%
Let x be the base amount.
Thus, we can write:
[tex]x + (15\% \times x ) = 55.20\\\\x + (\dfrac{15}{100}\times x) = 55.20\\\\x + 0.15x = 55.20\\1.15x = 55.20\\\\x = \dfrac{55.20}{1.15}\\\\x = 48[/tex]
Thus, the base amount is $48.