Here's how you add
Since our denominators match, we can add the numerators.
4 + 2 = 6
This yields the answer
The last step is to reduce the fraction if we can.
To find out, we try dividing it by 2...
Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:
So far so good... let's try to divide by that number again.
No good. So next you try the next prime number, which is 3...
No good. So next you try the next prime number, which is 5...
No good. 5 is larger than 3. So we're done reducing.
And we're done! Here's the final answer to 4/10 + 2/10