Question

the cost of a pen is half that of a book if both cost $15 the cost od a book is
​

Answer 1

Answer:

10

Step-by-step explanation:

because half of 10 is 5 so the pen is 5

5+10 is 15 so we know its true

Answer 2

Answer:

let cost of pen = x

then cost of book = x × 2

atq, x + x × 2 = 15

x + 2x = 15

3x = 15

x = 15 ÷ 3 = 5

therefore cost of the pen = $ 5

and cost of the book = $ (5 × 2) =$10

Mark my answer as the Brainliest and follow me.