Answer:
Polly has 10 yo-yos.
Step-by-step explanation:
Since Eureka has 20 yo-yos, and has twice as many yo-yos as Polly, to determine the number of yo-yos that Polly has it is necessary to perform the following equation:
Polly's Yo-yos = X
Eureka's Yo-yos = 2X
20 = 2X
20/2 = X
10 = X
Therefore, Polly has 10 Yo-yos, half the number Eureka has.
