A Square Multiplied By A Square = A Perfect Square & Other Facts

[Ndindu]

4 x 9 = 36

49 x 1 = 49

16 x 4 = 64 etc

A number is divisible by 3 if the sum total of its digits is divisible by 3 e.g 18. 1+8=9, 9/3=3 etc

In a room of 23 people there is 99% chance two people have the same birthday. Tafakari

“Eleven plus two” is an anagram of “twelve plus one” which is pretty fitting as the answer to both equations is 13.

-40 °C is equal to -40 °F.

[Kemoi]

not following

[Ndindu]

11+2=12+1

[Anon254]

1. (a)^2 x (b)^2 = (ab)^2
2. Divisibility rule. https://math.stackexchange.com/questions/341202/how-to-prove-the-divisibility-rule-for-3-casting-out-threes
   3Wrong that’s the. Birthday paradox. (1-(364/365)^(253))*100 = 50.047715403% chance
3. 13+2 =12+3, 10+1=11+0, 13+1 =11+3, 11+9=19+1, 99+1=91+9 etc not special. any two digit number added to a single digit does the same.
   proof:
   given three numbers a ,b and c between 0 and 9
   (10a+b) + c =10a +b +c = (10a+c) +b

5.(-40°F − 32) × 5/9 = -40°C

[Koolibah]

@Anon254

1. (a)^2 x (b)^2 = (ab)^2
2. Divisibility rule. elementary number theory - How to prove the divisibility rule for $3\, $ [casting out threes] - Mathematics Stack Exchange
   3Wrong that’s the. Birthday paradox. (1-(364/365)^(253))*100 = 50.047715403% chance
3. 13+2 =12+3, 10+1=11+0, 13+1 =11+3, 11+9=19+1, 99+1=91+9 etc not special. any two digit number added to a single digit does the same.
   proof:
   given three numbers a ,b and c between 0 and 9
   (10a+b) + c =10a +b +c = (10a+c) +b

5.(-40°F − 32) × 5/9 = -40°C

Now, this is the riddle