Random Riddles
What has to be broken before you can use it?
An egg
Function C takes time for its input and gives a student's Monday class for its output.
Use function notation to represent: A student has English as 10:00
C(10)=English
A new bicycle sells for $300. It is on sale for 1/4 off the regular price. Write an expression to represent the sale price of the bicycle in dollars.
300(3/4)
300(1 - 1/4)
300 - 1/4(300)
Solve using substitution.
y = 6x+11
2x - 3y = 7
(-2.5, -4)
Two inequalities are graphed on the same coordinate plane. Explain how to determine the solution to the system of two inequalities?
The solution is region where both inequalities overlap the other when shading in.
What begins with T, finishes with T, and has T in it?
A percent of voters between the ages of 18 and 29 that participated in each U.S. presidential election between the years 1988 and 2016 are shown in the table.
Year: 1988 1992 1996 2000 2004 2008 2012 2016
%: 35.7 42.7 33.1 34.5 45 48.4 40.9 43.3
Determine the average rate of change for P between 1992 and 2000.
P(t) decreased 1.025% per year between 1992 and 2000.
Write an expression answering the following question. The expression should only use multiplication.
A telephone costs $250. The sales tax is 7.5%. What was the cost of the telephone including sales tax?
250(1.075)
Solve without graphing.
5x+14y = -5
-3x+10y = 72
(-11.5, 3.75)
The sum of two numbers is less than 10. If we subtract the second number from the first, the difference is greater than 3. Write a system of inequalities that represents this situation. State what your variables represent.
f + s < 10
f - s > 3
f = the first number
s = the second number
What goes up but never comes back down?
Your age
To raise funds for a trip, members of a high school math club are holding a game night in the gym. They sell tickets at $5 per person. The gym holds a maximum of 250 people. The amount of money raised is a function of the number of tickets sold. What is the domain of the function?
All positive integers less than or equal to 250
The value of a home in 2015 was $400,000. Its value has been double each decade. If v is the value of the home, in dollars, write an equation for v in terms of d, the number of decades since 2015.
v = 400,000(2)^d
How many solutions does this system of equations have? Explain how you know.
9x - 3y = -6
5y = 15x + 10
5y = 15x + 10Infinitely many solutions. Both equations can be written as y = 3x + 2, so there graphs are exactly the same.
Select all of the x and y pairs that are solutions to the system of inequalities:
y ≤ -2x + 6
x - y < 6
A. (0, 0)
B. (-5, -15)
C. (4, -2)
D. (3, 0)
E. (10, 0)
A & D
(0, 0) & (3, 0)
No matter what, what can you always count on?
Your fingers
Each equation represents a function. For each, find its inverse.
c = w + 3
y = 5x
w = c - 3
x = y/5
The number of trees in a rainforest decreases each month by 0.5%. The forest currently has 2.5 billion trees. Write an expression to represent how many trees will be left in 10 years. Then, evaluate the expression.
2.5(0.0995)^12(10) or about 1.37 billion trees
Solve using elimination.
3x - 5y = 4
-2x + 6y = 18
(14.25, 7.75)
Julie has $200 to spend on flowers for a school celebration. She decides that the only flowers she wants to buy are roses and carnations. Roses costs $1.45 each and carnations costs $0.65 each. Julie buys enough roses so that each of the 75 people attending the event can take home at least one rose. Write a system of inequalities that represent the constraint that every person takes home at least one rose and to represent the cost constraint.
r ≥ 75
1.45r +0.65c ≤ 200
What is full of holes but still holds water?
Sponge
Functions h and j are inverses. When x is -10, the value of h(x) is 7 or h(-10)=7.
What is the value of j(7)?
Determine if each point is on the graph of h, on the graph of j, or neither.
(-10, 7)
(7, -10)
j(7)=-10
(-10, 7) is on the graph of h. When the input to h is -10, the output is 7.
(7, -10) is on the graph of j. When the input to j is 7, the output is -10.
A credit card has a nominal annual interest rate of 18%, and interest is compounded monthly. The cardholder uses the card to make a $30 purchase. Write an expression that represents the balance on the card after 5 years, in dollars, assuming no further charges or payments are made.
30(1 + 0.18/12)^5(12)
Solve.
-7x + 3y = -65
-7x + 10y = -135
(5, -10)
Jada has p pennies and n nickels that add up to more than 40 cents. She has fewer than 20 coins altogether. Write a system of inequalities that represent how many pennies and nickels that Jada could have.
0.01p + 0.05n > 0.40
p + n < 20