```{r, include = FALSE}
a <- sample(31:59, 1)
b <- sample(11:(a-10), 1)
sol <- 2 * b
```

Question
========
By how much is the sum of the numbers `r a` and `r b` greater than
the difference between these numbers?

Solution
========
The result of the calculation is
(`r a` + `r b`) - (`r a` - `r b`) = `r a + b` - `r a - b` = `r sol`.

Meta-information
================
exname: sum minus difference
extype: num
exsolution: `r sol`
extol: 0