Algebra
Geometry and Trigonometry
Probability
Calculus
Black History
100
If 3x + 2y = 16 and x - y = 2, what is the value of x + y?
6
100
In a right triangle ABC with right angle C, the angle A = 30 degrees, if the hypotenuse AB = 12 cm, what is the length of side AC?
6 * sqrt(3)
100
A bag contains 5 red marbles, 4 blue marbles, and 3 green marbles. Three marbles are drawn at random one after another without replacement. What is the probability that at least one of the drawn marbles is red?
37/44
100
limx->3(x2-9)/(x-3)
6
100
A famous botanist, scientist and educator who did a great work with peanuts.
George Washington Carver
200
Simplify the following expression for x > 0:
(x3*x-1)2/(sqrt(x6))
x
200
A circle has a radius of 6 cm. What is the area of a sector formed by a central angle of 60 degrees?
6pi cm2
200
Two standard six-sided dice are rolled. What is the probability that the sum of the numbers showing is equal to 7?
1/6
200
f(x) = 4x3 - 5x2 + 7x -2
f''(2) = ?
31
200
Invented the Supersoaker, a popular toy that showcases engineering creativity.
Lonnie G. Johnson
300
What is the minimum value attained by the quadratic function f(x) = 2x2 - 12x + 11?
-7
300
A rectangle with a width of 6 and a height of 8 is inscribed in a circle such that all four vertices touch the circle. What is the circumference of the circle?
10pi
300
A drawer contains 6 black socks and 4 white socks. You pull out one sock and then, without putting it back, pull out a second sock. What is the probability that both socks are white?
2/15
300
f(x) = x2/(x+1)
f'(x) = ?
(x2+2x)/(x+1)2
300
Created the traffic signal, improving road safety.
Garrett Morgan
400
log2(x)+log2(x-6)=4
8
400
If sin(a) =3/5 and angle a is in Quadrant II (90 degrees < a < 180 degrees), what is the value of tan(a)?
-3/4
400
A fair coin is flipped 3 times in a row. What is the probability of getting at least two heads?
1/2
400
f(x) = (2x-1)4
f'(1) = ?
96
400
Developed the electric carbon filament, enhancing light bulb efficiency.
Lewis Latimer
500
If r and s are the roots of the quadratic equation 2x2 - 7x + 4 = 0, what is the value of 1/r + 1/s?
7/4
500
In triangle ABC, side a = 5, side b = 8, and the included angle C = 60 degrees. What is the length of side c?
7
500
A jar contains 3 red candies and 5 blue candies. If you randomly pick 2 candies out of the jar one at a time without replacement, what is the probability that at least one of them is red?
9/14
500
lim(x->infinity) = (6x2-5x+1)/(2x2+3)
3
500
Invented the first home security system, laying the groundwork for modern security technology.
Marie van Brittan Brown