Answer:
300 watermelons
Step-by-step explanation:
3:2 ratio
3 is water melons and 2 is mangoes.
200 mangoes were purchased.
200/2=100
The unit rate is 100, so multiply 3 by 100, which is 300.
So Jack bought 300 watermelons, and 298 of which will be devoured by yours truly.
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hope it helps