Riddles
A four digit number is a multiple of 1,000. The thousands place is a prime number. What number could it be?
2000, 3000, 5000, 7000
How many degrees is a right angle?
90
n + 13 = 25
n = 12
6 ft = ___ inches
72
Make a factor rainbow for 24
1, 2, 3, 4, 6, 8, 12, 24
Think of a number between 1-100. It is a multiple of 5. If you add the ones and tens place together, it equals 10. What number is it?
55
What do you call an angle that is bigger than a right angle?
Obtuse
n/2 = 2/4
n = 1
5 meters = ___ centimeters
500
Are 29, 39, 49 prime numbers?
Only 29
A four digit number has all even digits. The ones place is twice as big as the tens place. The tens place is twice as big as the 100s place. What is the number?
6248
How many right angles can fit in a circle?
4 x 90 = 360
n x 25 = (10 x 25) + (2 x 25)
n = 12
36 inches = ___ yards
1
N is a multiple of 2, 3, and 5. N < 50. What is N?
30
A four digit number has an even prime number in the 1000s place. Then 100s place digit is twice as big as the 1000s. The 10s place is odd but not a prime number. The 1s place is not a prime or a composite number.
2491
Two angles put together make a half circle. If you know one angle = 45 degrees, what is the other one?
135
25 < n x 4 < 30
n = 7
4.2 kilometers = ____ meters
4200
What is the smallest number that has 6 factors?
12
13 x 24 = 312
What fraction of a circle is a 45 degree angle? You can use a denominator of 360 or a different one that works.
45/360 =1/8
1 < 1/4 x n < 1.5
n = 5
3 gallons = ____ quarts = ___ pints = ____ cups = ____ oz. 1 gal = 4q; 1 q = 2p; 1p =2c; 1c = 8oz
12q = 24p = 48c = 384oz
I have an odd number of factors and if you add my digits together I equal 9. What number am I?
36, 81