Answer: 51.25 cups
Explanation:
From the statement above, 20.5 cups is 0.4 of the entire amount of batter
let x = the total amount of batter.
Interpreting the above question mathematically;
0.4 of x = 20.5
0.4 × x = 20.5
0.4x = 20.5
divide both-side of the equation by 0.4, in order for the x variable to stand alone
0.4x/0.4 = 20.5/0.4
x = 51.25
Therefore 51.25 cups of batter are needed.