Why is $\frac{987654321}{123456789}$ almost exactly $8$?
60411
Why is $\frac{987654321}{123456789} = 8.0000000729?!$
138890
Cool property of the number $24$
27969
Why does $\frac{1}{x} < 4$ have two answers?
49443
What is the value of $\arctan(1/2)+\arctan(1/5)+\arctan(1/8)$?
68400
Proof that $\frac{(2n)!}{2^n}$ is integer
4967
Fractions with large elements
146358
Why is there a $\frac 1 2$ in $\frac 1 2 mv^2$?
64941
Why is $1 - \frac{1}{1 - \frac{1}{1 - \ldots}}$ not real?
72620
Finding the value of $1.1^{82}$ using $(1+x)^{82}$ to a certain accuracy
9343
Why does $\frac{1 }{ 99989999}$ generate the Fibonacci sequence?
28957
Verifying that $2^{44}-1$ is divisible by $89$
95702
Remarkable/unexpected rational numbers
138492
Finding the sum of the infinite series whose general term is not easy to visualize: $\frac16+\frac5{6\cdot12}+\frac{5\cdot8}{6\cdot12\cdot18}+\cdots$
119651
Expressing $1.24\overline{123}=1.24\;123\;123\;123\;\ldots$ as the ratio of two integers
17766
Find $n^{th}$ term of $\frac23,\frac35,\frac58,\frac8{13}\dots$
56974
Determining the missing digits of $15! \equiv 1\square0767436\square000$ without actually calculating the factorial
286
Is it true that $0.999999999\ldots=1$?