Need help with quadratics (1 Viewer)

[big_bang344]

Q) The bill for a group of friends at a restaurant totals to $180. This was to be shared equally but two had left early which caused the remaining guests to pay an extra $3 each. Calculate the amount paid by each of the remaining guests. Help please

Note: We're supposed to solve it quadraticly. :L

 

[funnytomato]

Q) The bill for a group of friends at a restaurant totals to $180. This was to be shared equally but two had left early which caused the remaining guests to pay an extra $3 each. Calculate the amount paid by each of the remaining guests. Help please

Note: We're supposed to solve it quadraticly. :L

srsly?

 

[big_bang344]

Yeh, and it was in our year ten topic test, but i posted it here because teachers told us it was ext 1 standard :L

 

[Drongoski]

Q) The bill for a group of friends at a restaurant totals to $180. This was to be shared equally but two had left early which caused the remaining guests to pay an extra $3 each. Calculate the amount paid by each of the remaining guests. Help please

Note: We're supposed to solve it quadraticly. :L

$18

Let group be of n friends.







.: remaining guests paid $180/(12-2) = $18 each.

 

[big_bang344]

Can you please show how you did it?

 

[funnytomato]

let the amout of money each person has to pay (after the 2 ppl dogged them) be x dollars

then you can express the number of ppl before they left in terms of x , since no. of ppl = total amout/individual amount
using the same principle, the number of ppl after they left can also be expressed in terms of x

find the difference bewteen these two numbers and equate it to 2

then you have a quadratic eqn after some simplifications

solve it using cross method or quadratic formula

 

[big_bang344]

Woah. Thanks!

 

[funnytomato]

i was gonna rep drongski's solution, but this "You must spread some Reputation around before giving it to Drongoski again." showed up

anyways, you can try to do it on your own using my method now

btw, I think it's more like a 2 unit question

 

[SpiralFlex]

Let be the amount of people and be the amount of money.

So before crazy guys left,





Now after crazy guys left,



Now substitute,

into the equation.



Expand,



Multiple all sides by and simplify,







This is how many guests remember? So after two have left, we have 10.

So, each will pay

I fell asleep reading this, literally.

 

[big_bang344]

Not getting enough sleep i see :L

 

[SpiralFlex]

Not getting enough sleep i see :L

You will understand this time next year, I have to travel far too.

 

[big_bang344]

Haha. True. Well, to be honest, i can't wait

 

[SpiralFlex]

Haha. True. Well, to be honest, i can't wait

Just like me during Year 10. All the best, by the way, I will be sending you papers soon like you asked so watch your inbox. I hope your question has been answered by these lovely fellas up the top. Goodnight.

 

[Drongoski]

I'm amazed at the number of ways to do it. Also thanks Mr Funny for trying to rep me again (after over 2 years, I've managed only 565 points!) and Mr SpiralFlex for your kind words.

 

[big_bang344]

Haha, thanks guys. Yeh, it is fascinating. That's one thing i love about maths. Only one right answer but so many ways to do it Gnights guys.

 

[maths lover]

$18

Let group be of n friends.







.: remaining guests paid $180/(12-2) = $18 each.

i seriously love this method. you must be so smart.