Marissa, Keith and Tony all go to Disneyland many times each summer. Together, they have all gone a total of 65 times. Marissa and Keith have gone 55 times total, while Keith and Tony have gone 40 times total. How many times has Keith gone just by himself?  Choose the correct choice from the following answers:
A) 30	B) 20	C) 25	D) 40	E) 10
Marissa + Keith + Tony = 65   M + K = 55   K + T = 40   Plug these each into the original formula   55 + T = 65   T = 10   Then, M + 40 = 65   M = 25   So, 25 + K + 10 = 65   Subtract 25 and 10 from each side to get Keith's total   K = 30   30nswer: 30
<result>A</result>
Marissa, Keith and Tony all go to Disneyland many times each summer. Together, they have all gone a total of 65 times. Marissa and Keith have gone 55 times total, while Keith and Tony have gone 40 times total. How many times has Keith gone just by himself?