We have to calculate the volume of the pond first
a = 25cm
b = 10cm
c = 15cm
a × b × c =
25cm × 10cm × 15cm =
[tex] {3750cm}^{3} [/tex]
3/5 of the pond is filled up, which means we still need to fill up 2/5 of the pond.
One fifth of the pond:
3750 ÷ 5 = 750
Two fifths of the pond:
750 × 2 = 1500
[tex]1500 {cm}^{3}[/tex]
^This is the final answer