Calculate the value of the given expression:

84 - 31 + 42 + (15 + 25) × 3 - 60 = ?

The correct answer is 155.

To evaluate the given mathematical expression, we follow the standard order of operations (BODMAS / PEMDAS): Brackets/Parentheses, Orders/Exponents, Multiplication and Division (from left to right), and Addition and Subtraction (from left to right).

Given expression:

$84-31+42+(15+25)\times 3-60$

Step 1: Simplify the terms inside the parentheses (brackets).

$15+25=40$

Substituting this back into the expression gives:

$84-31+42+40\times 3-60$

Step 2: Perform the multiplication operation.

$40\times 3=120$

Substituting this product into the expression gives:

$84-31+42+120-60$

Step 3: Perform addition and subtraction sequentially from left to right.

First operation ($84-31$):

$84-31=53$

Second operation ($53+42$):

$53+42=95$

Third operation ($95+120$):

$95+120=215$

Final operation ($215-60$):

$215-60=155$

Thus, the final calculated value of the expression is 155.