Question

Evaluate the expression. Justify each of your steps.

$1.25 + 1.38 + 0.75$

Short answer

$1.25+1.38+0.75 = 3.38$.

Step-by-step solution

Step-1 – What are real numbers? 

Real numbers are simply the combination of Whole numbers, Integers, Rational and Irrational numbers in the number system.

Step-2 – Associative Property of Addition of Real Numbers: 

Suppose a, b, and c is three real numbers.

Associative property of Addition: (a + b) + c = a + (b + c)

If you are adding three real numbers, the sum is always the same regardless of their grouping.

Example: (11+12) + 13 = 11 + (12+13) = 36

Step-3 – Evaluate the expression, Justify each of your steps. 1.25 + 1.38 + 0.75 

Associative property of Addition states, if you are adding three real numbers, the sum is always the same regardless of their grouping.

Name of the property for this equation 4 + (3 + 9) = (4 + 3) + 9 is Associative property of Addition.

According to the above property, we can evaluate the expression:

$\begin{array}{l}1.25+1.38+0.75\\ 1.25+(1.38+0.75)(\text{AssociativePropertyofAddition)}\\ \text{(1.25+1.38)+0.75}(\text{AssociativePropertyofAddition)}\\ \text{2.63+}0.75\text{=}3.38\end{array}$

$1.25+1.38+0.75 = 3.38$