Frank will pay $20 x 1/4 = $<<20*1/4=5>>5 for the joystick.
Eman will pay $20 - $5 = $<<20-5=15>>15 for the joystick.
So, Frank will pay a total of $140 + $5 = $<<140+5=145>>145.
While Eman will pay a total of $100 + $15 = $<<100+15=115>>115.
Therefore, Frank will spend $145 - $115 = $<<145-115=30>>30 more than Eman.
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