a. \( \frac{1}{5}+\frac{1}{5} \) b. \( 42,58+76,923+3,964 \)

When you add \( \frac{1}{5}+\frac{1}{5} \), you're simply bringing two parts together! Since both fractions have the same denominator, you can add the numerators: \( \frac{1+1}{5} = \frac{2}{5} \). So, you now have two fifths – think of it like having two slices out of a five-slice pizza! For the second calculation, add \( 42.58 + 76.923 + 3.964 \). Start by lining up the decimal points: ``` 42.580 76.923 + 3.964 __________ 123.467 ``` So, the sum of these three numbers is \( 123.467 \). Such a satisfying number – it's like finding the perfect recipe!