Question

John spend a total of sh 970 on buying 3 textbooks and 5pens if he had bought 2 textbook and 8 pens he would have saved sh90,find the cost of one textbook and one pen

Answer 1

Let:

X=Textbook price

Y=Pen price

3X+5Y=970  --------- {1}

2X+8Y=(970-90)=880  -----------{2}

Multiply equation one by 2

Multiply equation two by 3

Then substract equation one from equation two

24Y-10Y=880×3-970×2

14Y=700   ;    Y=50

By substitution in equation two

X=240.