4²+5[61-(5×6)] what's the answer for this

In this question we can see that there are different type of brackets used. Also there is multiplication addition and subtraction. So we need to follow the BODMAS rule.
B = Bracket
O = Of
D = Division
M = Multiplication
A = Addition
S = Subtraction
Now let us focus on the problem in hand.
4^2 + 5[ 61 - (5 * 6)] = (4)^2 + 5[ 61 - (30)]
                                 = (4)^2 + 5[ 61 - 30]
                                 = 16 + 5 [31]
                                 = 16 + 155
                                 = 171
So the answer for the question comes out to be 171. I hope the procedure is clear enough for you to understand. You can always use this method for solving similar problems in future.

If you would like to solve 4^2 + 5 * [61 - (5 * 6)], you can calculate this using the following steps:

4^2 + 5 * [61 - (5 * 6)] = 16 + 5 * [61 - 30] = 16 + 5 * 31 = 16 + 155 = 171

The correct result would be 171.

The surface area would be 576 because you multiply all the numbers then multiply that number by 6