Answer:
your rate of change was 40%
Step-by-step explanation:
Let x be ml of 5% soln.
let 500-x be ml of 25% soln.
.
x*.05=.05x
(500-x)*.25=125-.25x
500*.20=100
.
.05x+125-.25x=100
-.2x=-25
x=-25/-.2
x=125 ml of 5% soln.
500-x=375 ml of 25% soln.
.
Check:
125*.05= 6.25
375*.25=93.75
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