Question

.
The sum of marks obtained by Kamal in English and mathematics is 40 in class
test of grade 10. If the marks which he got in mathematics are increased by 3 and
marks which he got in English decreased by 4 then the product of marks is 360.
Find the marks obtained by him in mathematics and English.​

Answer 1

Let the marks scored in maths be X.

Marks in English is 40−X.

As, per the question,

If he got 3 marks more in maths & 4 marks less in English,

Marks in Maths =X+3

Marks in English =40−X−4=36−X

Product =360

(36−X)(X+3)=360

(36X+108−X

2

−3X)=360

(33X+108−X

2

)=360

X

2

−33X+360−108=0

X

2

−33X+252=0

X

2

−21X−12X+252=0

X(X−21)−12(X−21)=0

(X−12)(X−21)=0

X=12or21

∴ If marks in Maths =12 then marks in English =40−12=28

If marks in Maths =21 then marks in English =40−21=19