Answer:
17 floors
Step-by-step explanation:
1 floor every 4 seconds.
90/4 = 22.5
40 - 22.5 = 17.5
17.5 is 17ish floors, and is the only answer that is close to 17 floors.
Assume a is not divisible by 10. (otherwise the problem is trivial).
<span>Define R(m) to be the remainder of a^m when divided by 10. </span>
<span>R can take on one of 9 possible values, namely, 1,2,...,9. </span>
<span>Now, consider R(1),R(2),......R(10). At least 2 of them must have the sames value (by the Pigeonhole Principle), say R(i) = R(j) ( j>i ) </span>
<span>Then, a^j - a^i is divisible by 10.</span>
BC is the answer love... have fun on that I-Ready Diagnostic
They’re complimentary angles (add up to 90)
