At a meeting of 100 geniuses, each genius was either a mathematical genius or a musical genius. At least 1 of the
math geniuses is older than age 15. If you were to choose
any 2 geniuses from the group, at least 1 of them would be
younger than 15 years of age. How many of the 100
geniuses are older than 15, and how many are younger than
15?

3/20

step-by-step explanation:

well, there are 20 outcomes, and 3 of them you want. so, 3/20

just get this app called photo math it should be able to do those

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.