Given:
descends at a rate of 320 feet per minute for 3 minutes.
320 feet per minute * 3 minutes = 960 feet
Total change in altitude is 960 feet. Since it is descending, I believe it would be a negative 960 feet.
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
The answer is A, it can't land on a number that doesn't exist.
