Word Problems Create and solve a system of equations to answer each word problem

Kristen spent $131 on shirts. Fancy shirts cost $28 and plain shirts cost $15. If Kristin bought a total of 7 shirts, how many of each kind did she buy?

#1 Let x = # of plain shirts Let y = # of "fancy" shirts (-15) x + y = 7 15x +28y =131 -15x -15y = -105 15x +28y =131 13y 13 y =2 x +2 = 7 -2 -2 x =5 Final Answer : 5 plain shirts and 2 fancy shirts

A piggy bank holds $3.35 worth of nickels and quarters. If there is a total of 19 coins in the piggy bank, find the number of nickels and the number of quarters in the piggy bank.

#2 Let x = # of nickels Let y = # of quarters (-5) x + y =19 5x +25y =335 -5x -5y = -95 5x +25y =335 x +12 =19 -12 -12 x = 7 20y 20 y =12 Final Answer : 7 nickels and 12 quarters

The debate club sells pizza after school as a fundraiser. Plain slices cost $1.50 while Meatball slices cost $2.50. The club sold a total of 82 slices of pizza and made a total of $173. How many plain slices and how many meatball slices did they sell?

#3 Let x = # of plain slices Let y = # of meatball slices (-1.5) x + y = 82 1.5x +2.5y =173 -1.5x -1.5y = -123 1.5x +2.5y =173 y =50 x +50 = 82 -50 -50 x =32 Final Answer : 32 plain slices and 50 meatball slices

There are 13 animals in a barn. Some are chickens and some are pigs. The animals have a combined total of 40 legs. How many of each animal is there?

#4 Let x = # of chickens Let y = # of pigs (-2) x + y =13 2x + 4y = 40 x + 7 =13 - 7 - 7 -2x -2y = -26 2x + 4y = 40 2y 2 y = 7 x = 6 Final Answer : 6 chickens and 7 pigs

I am thinking of two numbers: The first number plus three times the second number equals 36. The second number is five more than two times the first number. Find both numbers.

#5 Let x = the first number Let y = the second number x +3y =36 y =2x +5 ( ) +5 y = 6+5 ) =36 x +6x +15 =36 y =11 7x +15 =36 -15 -15 7x 7 x =3 Final Answer : The first number is 3 and the second number is 11