1 3/10+2 1/7+2/5

You need to find a common denominator (70) and multiply the numerator by the amount of times you multiplied the denominator. It may sound tricky, but trust me, it helps!

http://www.mathsisfun.com/fractions_addition.html

To add mixed numbers with fractions, you need to convert the mixed numbers into improper fractions, then find a common denominator, and finally add the fractions.

Let's break down the steps to solve `1 3/10 + 2 1/7 + 2/5`:

Step 1: Convert the mixed numbers into improper fractions.
- `1 3/10` can be converted to an improper fraction as `(1 * 10 + 3)/10 = 13/10`.
- `2 1/7` can be converted to an improper fraction as `(2 * 7 + 1)/7 = 15/7`.

Now, the expression becomes `13/10 + 15/7 + 2/5`.

Step 2: Find a common denominator.
To add the fractions, we need to find a common denominator. In this case, we can use `70` as the common denominator because it is divisible by `10`, `7`, and `5`.

- Multiply the numerator and denominator of `13/10` by `7` to get `91/70`.
- Multiply the numerator and denominator of `15/7` by `10` to get `150/70`.
- Keep the fraction `2/5` as it is.

Now, the expression becomes `91/70 + 150/70 + 2/5`.

Step 3: Add the fractions.
Add the numerators together and keep the common denominator to get the final fraction.

- `(91 + 150 + 2)/70 = 243/70`.

So, `1 3/10 + 2 1/7 + 2/5` equals `243/70`.