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Thread: Four two go!

20041111, 12:15 #1
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Four two go!
1. A farmer knows that 20 of his hens, housed in 3 coops, will hatch 30 eggs in 18 days. How long will it take 30 hens, housed in 4 coops to hatch the same number of eggs?
2. A car travels at a speed of 30 mph over a certain distance, and then returns over the same distance at a speed of 20 mph. What is the average speed for the total trip?
3. Find a simple method of solving:
6751X + 3249Y = 26751
3249X + 6751Y = 23249
4. A jar has 4 amoebas in it to start. Amoebas split their cells in two ( therefore doubling in size) once every minute. The jar will be completely filled in 10 minutes. How long would it take to fill the same sized jar if had 8 amoebas in it to start?Regards,
Rudi

20041111, 12:28 #2
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Re: Four two go!
4 <span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">9min</span hide>
Steve

20041111, 12:31 #3
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Re: Four two go!
2 <span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">24 mph</span hide>
Steve

20041111, 12:39 #4
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Re: Four two go!
3) <span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold"> I get X = 3, Y = 2. My "simple way" was to use excel matrix functions: MInvers and MMult.</span hide>
Steve

20041111, 12:41 #5
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Re: Four two go!
1<span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">12 days = 18days * 20 hens/30 hens</span hide>
Steve

20041111, 13:04 #6
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Re: Four two go!
Yo Steve,
You are spot on with 2, 3, and 4. <img src=/S/thumbup.gif border=0 alt=thumbup width=15 height=15>
If your answer for #1 is <span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">12</span hide>, then according to my answer you are incorrect!Regards,
Rudi

20041111, 13:11 #7
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Re: Four two go!
1 <span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">The time taken for the eggs to hatch is fixed, so 18 days</span hide>

20041111, 13:16 #8
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Re: Four two go!
<span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold"> 1. 18 days</span hide>
Jerry

20041111, 13:20 #9
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Re: Four two go!
<span style="backgroundcolor: #FFFF00; color: #FFFF00; fontweight: bold">3.
1) Add the equations to give: 10000X + 10000Y = 50000
2) Divide by 10000 to give: X + Y = 5
3)Subtract to give: 3502X  3502Y = 3502
4) Divide by 3502 to give: X  Y = 1
5)Therefore: X = 3 and Y = 2
</span hide>Jerry

20041111, 13:49 #10
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Re: Four two go!
Thats it Steve.
Good Jezza...spot on too!Regards,
Rudi