Question

Steven has 57 coins in his piggy bank. He only puts pennies and nickels inside. If he has $1.85, how many pennies does he have?

Answer 1

25

28

31

32

Answer 2

nickels are 5, pennies are 1
if you put say \(x\) as the number of nickels then they give you \(5x\) cents
since there are 57 coins altogether if there are \(x\) nickels there are \(57-x\) pennies, which are obviously on cent each
total cents is therefore
\[5x+(57-x)\] and you know the total is 185 so set
\[5x+(57-x)=185\] and solve for \(x\)

Answer 3

5x+(57-x)=185
I know i am supposed to start in te parenthesis im just not sure what to do first

Answer 4

your teacher may have wanted you to write a system of equations
put \(x\) as the number of nickels, \(y\) as the number of pennies and then you get two equations
\[x+y=57\] and
\[5x+y=185\] but then you would solve this by solving the first equation for \(y\) toget
\[y=57-x\] substitute it in to the second equation to get
\[5x+(57-x)=185\] and so you see that you get the same equation
can you solve that one?

Answer 5

do you subtract 5x from both sides?

Answer 6

no you should take 4 steps to do this
remove parentheses
\[5x+57-x=185\] now combine like terms
what do you get?

Answer 7

-6x+57=185

Answer 8

oops
what is \(5-1\) ?

Answer 9

haha whoops 4x+57=185

Answer 10

yes
now two more steps
any ideas or you want me to tell you?

Answer 11

I think I have to subtract 4x from both sides. ?

Answer 12

nope that cant be right

Answer 13

ok lets go slow
you want to get \(x\) by itself
so you want all the \(x\) on one side of the equal sign and the number on the other
so what you need to do is to first subtract \(57\) from both sides

Answer 14

yes, you no not want to subtract \(4x\) from both sides, that just puts a \(-4x\) on the other side
no help

Answer 15

I swear i was gonna say that first but it didnt look right lol. yay :)
4x+57=180
-57 -57
4x=123
/4 4
x=30.75?

Answer 16

so 31 :) ?

Answer 17

well the reason it doesn't look right is because the right hand side was \(185\) not \(180\)

Answer 18

you are asked for the number of nickels and the number of pennies, so your answer should be a whole number, not a decimal

Answer 19

haha oh geez. 4x+57=185
-57 -57
4x=128
/4 /4
x=32

Answer 20

now that looks good
therefore there are 32 nickels and also 25 pennies

Answer 21

thankyoU! :)

Answer 22

yw