Answer:
The answer is 900 ×6= 5,400 u can use a calculator
This should be the equation:
n + 4/3n + 5/3n = 90
42.86% error was in the scientist's estimation.
Step-by-step explanation:
Given data;
Approx amount = 4 ml
Exact amount needed = 7 ml
Percentage error = 

42.86% error was in the scientist's estimation.
Keywords: error, percentage
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