Kristen completed 42 km. We will imagine that she ran all 6 hours. => 9 * 6 =54 km which is more than she actually completed. So we will find a 9 Multiple less than 42 km and that will be 36 km. (9 * 4 = 36 km completed by running) and the rest until 42 were completed by walking (3 * 2 = 6; 6 + 36 =42).
<span>18/37 if you're in Europe, 9/19 if you're in America, assuming the wheel isn't rigged.
If the roulette wheel is a fair wheel, the odds on any given spin of the wheel is unaffected by any previous spins of the wheel. So no matter how many times the wheel has consecutively come up red, the next spin can still come up red, black, or green based upon the number of each color is present on the wheel. The difference between the odds for Europe vs America has to do with a quirk about roulette. In Europe, the roulette wheel has 37 slots, 18 red, 18 black, and 1 green. In America, the roulette wheel has 38 slots, 18 red, 18 black, and 2 green.
Although in this case, I'd be wary about assuming that the wheel isn't rigged. The odds of 270 consecutive red on a fair wheel is only 1 in 3.09663x10^84 in Europe, or 1 in 4.14949x10^87 in America.</span>
5. The 5th figure will have 30 tiles.
6. The 6th figure will have 42 tiles.
7. The pattern is non-linear (quadratic).
8. The 20th figure can be made with 420 tiles.
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The Nth figure is made with n*(n+1) tiles. To answer question 8, you must solve
.. n(n +1) = 420
.. n^2 +n -420 = 0
.. (n +21)(n -20) = 0
.. n = 20 or -21 . . . . the negative solution is extraneous
