Six people are planning a five day backpacking trip. The trail they will take is 67 miles long. Everyone 12 and older will carry a 40-pound pack. Everyone younger will carry a 20-pound pack. What is the total weight (in pounds) of the groups backpack? The answer I got is 12 and older 3x40=120 everyone younger 3x20=60. 120+60=180 is this right. This is what they want (1)140 (2) 160 (3)180 (4) 200 (5) not enough information is given
3 answers
But the problem doesn't tell us how many were 12 and older.
number over 12 ---- x
number under 12 ---- 6-x
total weight = 20x + 40(6-x)
= 20x + 240 - 40x
= 240 - 20x
now we know that x is a whole number from 0 to 6
x --- weight
0 240
1 220
2 200
3 180
4 160
5 140
6 120
All the answers they give are possible, so clearly they did not give us enough information.
notice that the fact it is a 5 day trip and 67 miles is totally irrelevant.
number under 12 ---- 6-x
total weight = 20x + 40(6-x)
= 20x + 240 - 40x
= 240 - 20x
now we know that x is a whole number from 0 to 6
x --- weight
0 240
1 220
2 200
3 180
4 160
5 140
6 120
All the answers they give are possible, so clearly they did not give us enough information.
notice that the fact it is a 5 day trip and 67 miles is totally irrelevant.
what is the total weight in pounds of group's backpacks