To start, we know that Farah puts 1 cantaloupe, 1 pineapple, and 1 mango in each of the 5 baskets. This means that she places 3 pieces of fruit (1 of each type) in each basket. Thus, the total number of these fruits used for all 5 baskets is:
\[ 5 \text{ baskets} \times 3 \text{ fruits/basket} = 15 \text{ fruits} \]
Now, we can calculate how many tangerines Farah can distribute. Since she has 55 total pieces of fruit, the number of tangerines she can distribute is:
\[ 55 \text{ total fruit} - 15 \text{ fruits} = 40 \text{ tangerines} \]
We can let \( x \) be the number of tangerines in each basket. Since there are 5 baskets, the total number of tangerines is:
\[ 5x \]
Now we can set up the equation that represents the total pieces of fruit:
\[ 15 + 5x = 55 \]
To solve for \( x \), we'll rearrange the equation:
\[ 5x = 55 - 15 \] \[ 5x = 40 \] \[ x = \frac{40}{5} \] \[ x = 8 \]
Thus, the equation representing the problem is:
\[ 15 + 5x = 55 \]
And the value of \( x \) once this equation is solved is \( x = 8 \), which means Farah puts 8 tangerines in each basket.