• Apr 12th 2011, 07:39 AM
JesseElFantasma
(Hi)

I have these Algebra Problems that I just do not understand. So far I understand the whole idea of what algebra is and variables, but I do not understand these problems.

http://i52.tinypic.com/2md3xjo.jpg

http://i53.tinypic.com/245zu6p.jpg

Your help would be greatly appreciated.

Thanks~! (Thinking)(Thinking)
• Apr 12th 2011, 07:47 AM
SpringFan25
taking the cooking time example:

"15 minutes + 35 minutes per kilogram"

This would be
for 1kg: t = 15 + (35*1)
for 2kg: t = 15 + (35*2)
for 3kg: t = 15 + (35*3)
for 4kg: t = 15 + (35*3)
...
for 10kg: t = 15 + (35*10)
...

What if i told you the number of kilograms was "x" insead of specifying the number
for xkg: t = 15 + (35*x)

The same approach may help on the other question
• Apr 12th 2011, 07:52 AM
JesseElFantasma
Quote:

Originally Posted by SpringFan25
taking the cooking time example:

"15 minutes + 35 minutes per kilogram"

This would be
for 1kg: t = 15 + (35*1)
for 2kg: t = 15 + (35*2)
for 3kg: t = 15 + (35*3)
for 4kg: t = 15 + (35*3)
...
for 10kg: t = 15 + (35*10)
...

What if i told you the number of kilograms was "x" insead of specifying the number
for xkg: t = 15 + (35*x)

The same approach may help on the other question

Thanks!

So if the variable for kg was m I would have to go : m kg: t= 15+ (35x2)
That would mean that the amount of kilo's is two. Right?
• Apr 12th 2011, 07:54 AM
HallsofIvy
The first one asks you to fill out a table showing how much remains to be paid off you are told they are 1000- 200, 1000- 200(2), 1000- 200(3), etc. What are those amounts? After the week 1 he still owes 1000- 200(1), after week 2 he still owes 1000- 200(2), after week 3 he still owes 1000- 200(3), after week 4 he still owes 1000- 2(4), etc. How much does he still owe after week n? Do you see where the "week number" fit into each of those? Replace that with n.

The second gives a recipe that says you must roast for 35 minutes for each kilogram plus an additional 15 minutes. If your roast weighed 2 kg, you roast it for 35 minutes for each kg: 2(35)= 70 minutes, then and additional 15 minutes: 70+ 15= 85 minutes. Suppose your roast weight 3 kg. How long would you cook it? What if it were four kg.? Think about what you did there. What if it were "x" kg.?
• Apr 12th 2011, 07:54 AM
SpringFan25
Quote:

Thanks!

So if the variable for kg was m I would have to go : m kg: t= 15+ (35x2)
That would mean that the amount of kilo's is two. Right?
yes, the formula for 2kg would be
t=15 + (35*2)

the formula for m kilos would be
t = 15 + (35*m)
• Apr 12th 2011, 08:00 AM
JesseElFantasma
Quote:

Originally Posted by HallsofIvy
The first one asks you to fill out a table showing how much remains to be paid off you are told they are 1000- 200, 1000- 200(2), 1000- 200(3), etc. What are those amounts? After the week 1 he still owes 1000- 200(1), after week 2 he still owes 1000- 200(2), after week 3 he still owes 1000- 200(3), after week 4 he still owes 1000- 2(4), etc. How much does he still owe after week n? Do you see where the "week number" fit into each of those? Replace that with n.

The second gives a recipe that says you must roast for 35 minutes for each kilogram plus an additional 15 minutes. If your roast weighed 2 kg, you roast it for 35 minutes for each kg: 2(35)= 70 minutes, then and additional 15 minutes: 70+ 15= 85 minutes. Suppose your roast weight 3 kg. How long would you cook it? What if it were four kg.? Think about what you did there. What if it were "x" kg.?

Thank you halls of Ivy.
I understand the second explanation, but I do not understand the 1st.
Must I go for month 4 : 80 000- (20 000 x t)

If so, what is that (A) for?

THANKS!
• Apr 12th 2011, 09:26 AM
Carlow52
Quote:

Originally Posted by JesseElFantasma
Thank you halls of Ivy.
I understand the second explanation, but I do not understand the 1st.
Must I go for month 4 : 80 000- (20 000 x t)

If so, what is that (A) for?

THANKS!

What (A) I dont see any A,and i dont see the numbers used by HoI either and I dont see any 20,000 so am a bit confused

original loan 80,000
repayment is 2,000 per month so at end of
month 1 its 80,000 - 2000= 78,000
Month 2 its 80,000 - 2,000 - 2,000 or 80,000 - (2,000 * 2)

Month n its 80,000 - (2,000*n)
• Apr 12th 2011, 09:30 AM
JesseElFantasma
Quote:

Originally Posted by Carlow52
What (A) I dont see any A,and i dont see the numbers used by HoI either and I dont see any 20,000 so am a bit confused

original loan 80,000
repayment is 2,000 per month so at end of
month 1 its 80,000 - 2000= 78,000
Month 2 its 80,000 - 2,000 - 2,000 or 80,000 - (2,000 * 2)

Month n its 80,000 - (2,000*n)

Thank you