64
Step-by-step explanation:

43% of 600 gallons of water is
258Convert your percentage into a decimal:

Multiply your decimal and 600:
Fraction: 1/512
decimal: 0.001953
X represent the number of laps Marcy swam, 114x represent the number of times Toni swam.
20 + 0.80(114x) + 15 + 0.85x = 257
20 + 91.2x + 15 + 0.85x = 257
92.05x + 35 = 257
Required equation is 92.05x + 35 = 257
60%=6/10
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