Respuesta :
Answer:
1.25
Step-by-step explanation (a):
Given expression:
[tex]-1.25+2.5[/tex]
A few changes were made to the expression.
Those were the following:
- This expression can be written as [tex]2.5 - 1.25[/tex].
- Let 2.5 be 2.50.
Subtract using column subtraction method:
[tex]4[/tex]
______________
[tex]2 \ \ . \ \ 5 \ \ \ \ \ 0[/tex]
[tex]- \ \ \ 1 \ \ . \ \ 2 \ \ \ \ \ 5[/tex]
______________
[tex]\ \ \ 1 \ \ . \ \ 2 \ \ \ \ \ 5[/tex]
Thus, the sum of −1.25 and 2.5 is 1.25.
Step-by-step explanation (b):
In this case, the first addend is the digit in the front of the expression.
⇒ a + b
⇒ a is the first addend
Thus, the first addend is -1.25.
The sum is the addition of two or more digits.
⇒ a + b = c
⇒ c is the sum
Thus, the sum is 1.25, which we calculated above.
Finally, let's plot the sum and the first addend on the number line.