Answer :

Certainly! Let's solve the arithmetic operation step-by-step to find the answer:

1. Step 1: Start with the first two numbers.
[tex]\[ -40 + 70 \][/tex]
Adding these together, we get:
[tex]\[ -40 + 70 = 30 \][/tex]

2. Step 2: Take the result from Step 1 and add the next number.
[tex]\[ 30 + 40 \][/tex]
Adding these together, we get:
[tex]\[ 30 + 40 = 70 \][/tex]

3. Step 3: Finally, take the result from Step 2 and subtract the last number.
[tex]\[ 70 - 90 \][/tex]
Subtracting these together, we get:
[tex]\[ 70 - 90 = -20 \][/tex]

So, the final result is:
[tex]\[ -40 + 70 + 40 - 90 = -20 \][/tex]