Geometry
Algebra
Probability
Number Theory
100
Find x.
10
100
x + 34 = 70
Find x.
x = 36
100
Two coins are tossed, find the probability that two heads are obtained.
1/4
100
Find the sum of the primes less than 20.
77
200
Find x.
√13 or sqrt(13)
200
x2 - 20x + 91 = 0
Find the sum of the possible values of x.
20
200
You have 10 balls, 5 of which are red, 3 of which are blue, and 2 of which are green. If you picked out 2 marbles without replacement, what is the probability you pick 2 red marbles?
2/9
200
How many zeroes are at the end of 25! (25 factorial)?
6
300
Find the length AB
sqrt(65)
300
x*(x + 2y) = 25 - y2
x2 - y2 = 10
Find xy.
21/4
300
If you have 4 basketball teams, called A, B, C, and D, and each team plays two other teams, what is the probability that A and B do not play each other?
1/3
300
Find all positive integers n such that n2 + 1 is divisible by n + 1.
1