Answer:
Only expression that's not equal to 30 is option 3 which is; (2 x 60 : 30) x (24 + 2)
Explanation:
We want to find which of the expression is not equal to 30.
1) (120 : 20) x (2+3)
Using BODMAS, we will solve the brackets first. So, we have;
(120/20) × 5
Note that a ratio implies division.
So, we have;
6 x 5 = 30
2) (9 x 10) : (4 + 1) + 12
Again, using BODMAS, solve the brackets first.
90 : 5 + 12
Ratio symbol is division and so it come before addition in BODMAS.
So, we have;
(90/5) + 12 = 18 + 12 = 30
3) (2 x 60 : 30) x (24 + 2)
Again, using BODMAS, solve the brackets first.
In the first bracket, we'll use division first before multiplication.
(2 x 60/30) x (26) =
2 x 2 x 26 = 104
4) 2 + (30 - 8:4)
Again, using BODMAS, solve the brackets first.
In the second bracket, division goes first. So,
2 + (30 - 8/4) = 2 + (30 - 2) = 2 + 28 = 30
So the only expression that's not equal to 30 is option 3 which is; (2 x 60 : 30) x (24 + 2)