Let's think of the rule of BIDMAS which stands for Bracket Indices Division Multiplication Addition and Subtraction
Without parentheses
8 + 30 ÷ 2 + 4 = 27
Because following BIDMAS, we would first do 30 ÷ 2 = 15
Then 8 + 15 + 4 = 27
We will need to put brackets at different places to equate the expression to 23 and 15 because the sum that is inside a bracket will have to be calculated first
(8 + 30) ÷ 2 + 4 = 38 ÷ 2 + 4 = 19 + 4 = 23
Here we first do the sum 8 + 30 = 38
Then the division 38 ÷ 2 = 19
Then the addition 19 + 4 = 23
8 + 30 ÷ (2 + 4) = 8 + 30 ÷ 6 = 8 + 5 = 13
Here we work out first the sum inside the bracket 2 + 4 = 6
Then we do 30 ÷ 6 = 5
And last 8 + 5 = 13