Riddles
What gets smaller every time it takes a bath?
soap
12 x 11 in your head
132
2x+5=17
x=6
Is this an arithmetic or geometric sequence:
3, 6, 12, 24, 48...
Geometric
I'm sweet and cold with a stick to hold; a treat on a hot day, worth more than gold. What am I?
A popsicle
47+68+29 in your head
144
3y−7=2y+5
y=12
What is an expression following the sequence?
3, 5, 7, 9, ...
2n+1
What word contains 26 letters but only has three syllables?
Alphabet.
36×25+48×25
2100
4(x−2)+3=3(2x+1)
x=-4
What is the 10th term of the sequence: 3,7,11,15,…
39
David's father has three sons: Snap, Crackle and _____?
David
74 x 66 (20 seconds)
4884
Find x and y:
2x+y=10
x−y=4
x=14/3 y=2/3
Find the sum of all single-digit numbers: 1+2+3+⋯+9
9 x 5 = 45
What is more useful when it is broken?
An egg.
What’s 15^2−14^2 without a calculator?
29
5^x+1 * 25^2-x = 5^5
x=0
What is the 11th term in this sequence:
1, 8, 27, 64, 125
1331