math 1
posted by HELP HELP HELP MNHS .
The total outing cost for a group of people amounted to Php 8000. When an additional 4 persons decided to join the outing, the cost per person decreased by 100. How many people actually joined the trip?

let number of people originally be n
cost per person = 8000/n
new count = n+4
new cost = 8000/(n+4)
8000/n  (8000/(n+4) = 100
times n(n+4)
8000(n+4)  8000n = 100n(n+4)
expand after dividing by 100
80n + 320  80n = n^2 + 4n
n^2 + 4n  320 = 0
(n+20)(n16) = 0
n = 16 or n=20 , but clearly n > 0
so originally 16 people had signed up, but 4 more joined,
So there were 20 people on the trip
check:
original cost = 8000/16 = 500
new cost = 8000/20 = 400
YUP! 
thanks Reiny, hope i am as intelligent as you.... :)
Respond to this Question
Similar Questions

12th grade calculus
your operate a tour service that offers the following rate: $200 per person if 50 people (the minimum number to book the tour) go on the tour for each additional person, up to a maximum of 80 people total, the rate per person is reduced … 
algebra
If Sam Stevens and four other friends want to schedule a 6 hour fishing trip on Lake Ontario with Reel Easy Sport Fishing. The cost for five people is $445. The cost for six people is 510. How much money per person will Sam and each … 
calculus
Maximimum profit: you operate a tour service that offers the following rates: (1) $200 per person if 50 people (the minimum number to book the tour) go on the tour. (2) for each additional person, up to the maximum of 80 people total, … 
algebra 2
A drama club is planning a bus trip to new york city to see a broadway play. the cost per person for the bus renatl varies inversely as the number of people going on the trip. It will cost $30 per person if 44 people go on the trip. … 
Math
On an outing to the theatre the tickets are £8.50 each for every ten tickets bought you get two extra free tickets. How much would it cost if you wished 12 tickets? 
math
A canoe rental company charges $10 for a canoe and an additional charge per person. there are 4 people going on trip and they have planned on spending total of $50. They hope that the total cost is within $20 of the planned spending … 
Math
A certain travel agency offered a tourthat will cost each person P 1500.00 if not more than 150 persons will join,however the cost per person will be reduced by P 5.00 per person in excessof 150. what will be the maximum profit? 
Algebra
Problem: The rock group Loco Moco was scheduled for a concert at the Blaisdell Concert Hall. Because it was the concert highlight of the year, there was excitement in the air and people were eager to get tickets, which could only be … 
Math  help please
Problem: The rock group Loco Moco was scheduled for a concert at the Blaisdell Concert Hall. Because it was the concert highlight of the year, there was excitement in the air and people were eager to get tickets, which could only be … 
Math
A group of 45 people decide to rent a bus for a trip. They divide the cost equally. When five of the people decide not to go on the trip the rest of the people pay $10 more each. How much does the bus cost?