Let T1 and T2 be random times for a company to complete two steps in a certain process. Say T1 and T2 are measured in days and they have the joint p.d.f. that is uniform over the space 1 < t1 < 10, 2 < t2 < 6, t1 + 2t2 < 14. What is the P( T1 + T2 > 10)?

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