Thirty percent of the members of a swim team have passed the lifesaving test. Among the members who have NOT pased the test, 12 have taken the prepatory course and 30 have not taken the course.. How many members are inthe swim club?
How do you get the conclusion?
2007-03-26 01:10:50 · 9 answers · asked by thatfella 1 in Science & Mathematics ➔ Mathematics
Hi,
If thirty percent of the members of a swim team have passed the lifesaving test, then 70% have not passed it. Among the members who have NOT passed the test,which is that 70%, 12 have taken the preparatory course and 30 have not taken the course.That means that 30 + 12 or 42 kids are 70% of the swim team. If we make that into an equation we'd get .7x = 42. Dividing both sides by .7, we get x = 60. So there are 60 members in the swim club?
You can also set up a proportion to find the number in the swim club.
70_____ 42
=== = ====
100_____X (underlines are for spacing)
Cross-multiplying 70X = 4200
Dividing by 70, X = 60.
I hope that help.
2007-03-26 01:20:17 · answer #1 · answered by Pi R Squared 7 · 1⤊ 0⤋
First, look at the people who have not passed the test
12 have taken the prepatory course and 30 have not taken the course, which means a total of 42 people have not passed the test.
Therefore 42 is 70% of the total number of members
42 = x * 70/100
42 * 100/70 = x
x = 60
There are 60 members.
2007-03-26 08:21:50 · answer #2 · answered by Tom :: Athier than Thou 6 · 0⤊ 0⤋
30% passed --> 70% failed
this 70% is made of 12 that took the course and 30 that didn't.
Therefore 42 (12+30) is the 70% of the total (100% of members that are in the club).
use ratios: 70:100=42:x x= 60(tot n. of members)
2007-03-26 08:20:13 · answer #3 · answered by Lara M. 3 · 0⤊ 0⤋
30+12=42 wich represents 70% of class
42/.7=60 ToTal
2007-03-26 08:23:26 · answer #4 · answered by ? 5 · 0⤊ 0⤋
the 70% = 12+30 = 42
so 100% = 60
The total number of students is 60
2007-03-26 11:35:10 · answer #5 · answered by Ahmed A 2 · 0⤊ 0⤋
Let the number of people in the swim club be x
Therefore,
x- 0.3x= 30+12
or, 0.7x= 42
or, x= 60
There are 60 members in the swim club
2007-03-26 08:40:08 · answer #6 · answered by Bubblez 3 · 0⤊ 0⤋
.3x + 30 + 12 = x
.7x = 42
x = 60
2007-03-26 08:15:43 · answer #7 · answered by metalluka 3 · 0⤊ 0⤋
only 42 have failed so therefore 70% is 42.
.7x = 42
x = 60 members
2007-03-26 08:22:50 · answer #8 · answered by geloi 2 · 0⤊ 0⤋
561/2
2007-03-26 08:15:49 · answer #9 · answered by Anonymous · 0⤊ 2⤋