Answer: the number is 10.
Explanation:
Let the missing number be p
From the question, p + 1/2p = 15
1 1/2p = 15
1 1/2p can be written as 3/2p
3/2p= 15
Divide both sides by 3/2
p = 15 ÷ 3/2 = 15 x 2/3
P= 30/3 = 10
If p is 10;
1/2p = 10/2 =5.
The number is 10.
I hope this helps.