Subjects

A student takes 5 minutes to complete a maths problem and 12 minutes to complete a biology problem. One day, he has a combined homework assignment of 11 problems that takes him one and a half hours to complete. How many problems are from each subject?

Final Answer:

b =  5
m =  6

Step-by-step explanation:

5m+12b = 1.5·60
m+b=11

5·m+12·b = 1.5·60
m+b=11

12b+5m = 90
b+m = 11

Row 2 - 1/12 · Row 1 → Row 2
12b+5m = 90
0.58m = 3.5


m = 3.5/0.58333333 = 6
b = 90-5m/12 = 90-5 · 6/12 = 5

b = 5
m = 6

Our linear equations calculator calculates it.

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