the average marks of 30 students in a class is 100 . but a student mark is wrongly noted as 70 instead of 10 then find the correct average marks ?
"correct avg marks = 100 + ( 10 - 70 ) / 30 avg = 100 - 2 = 98 answer is c"
divide(add(subtract(multiply(100, 30), 70), 10), 30)