The ratio of fruit juice to lemonade in the second batch is 21:16
<h3>What are ratios?</h3>
Ratios are denoted by the sign ":", and they are used to making comparison between units of different quantities
The ratio is given as:

Where:
- F represents the amount of fruit juice
- L represents the amount of lemonade
When 2 litres are added to the original amount of lemonade, the ratio becomes

Hence, the ratio of fruit juice to lemonade in the second batch is 21:16
Read more about ratios at:
brainly.com/question/2784798