# Trying to help my daughter with algebra i need help

#### sandbugee

##### New member
hi

My daughter is struggling with her algebra home work especiall with the word problems i was wondering if anyone had any suggestions on how to help her.. for example she had a word problem that stated

if you have an income of 4140.00 and you budget 2/10 for rent and 14/20 for other needs how much would you have left..Or how much is alloted maybe thats it ?? please help.

I think that is how it went..

she is also having problems solving equations like

4 + 7 11
n N 8

how would you go about solving these types of equations.

thank you for your help

#### sandbugee

##### New member
sorry need to add somethin

7 +11 + 9
n n 8

i think thats how the problem went[/list][/list]

#### wjm11

##### Senior Member
if you have an income of 4140.00 and you budget 2/10 for rent and 14/20 for other needs how much would you have left.
2/10 + 14/10 = 2/10 + 7/10 = 9/10

That is, 90% of the money goes to rent and other needs. What's left is

1 - 9/10 = 1/10 (or 10% of your income)

7 + 11 + 9
n n 8
This second problem is not an equation (notice there's no equal sign.). It's an expression that , perhaps, you're supposed to simplify(?).

7/n + 11/n + 9/8

To simplify (make into a single fraction), first find the LCM: n*8 = 8n
Therefore, to get each fraction over a common denominator, multiply the first two terms by (8/8) and the third term by (n/n):

(7*8)/8n + (11*8)/8n + 9n/8n = (56 + 88 + 9n)/(8n) = (144 + 9n)/8n

Is this what you're looking for?

#### sandbugee

##### New member
thank you for your help

Thanks for the help this does help me understand it a little better so i can help her..

can you tell me if im doing this right or showing her right

21 5/10
35 2/7
32 2/5

i told her to change the denominator to 70 then multiply the top part of the fractions like 5 x 7 =35 then 2 x 14= 28 and 2 x 14 =28 so it would look like this

21 35/70
35 14/70
32 28/70

but then thats where i get stuck on how to add them

would it be 88 77/70 ?? and then reduced to 88 7/10

#### Denis

##### Senior Member
Re: thank you for your help

sandbugee said:
Thanks for the help this does help me understand it a little better so i can help her..
can you tell me if im doing this right or showing her right
21 5/10
35 2/7
32 2/5
i told her to change the denominator to 70 then multiply the top part of the fractions like 5 x 7 =35 then 2 x 14= 28 and 2 x 14 =28 so it would look like this
21 35/70
35 14/70
32 28/70
but then thats where i get stuck on how to add them
would it be 88 77/70 ?? and then reduced to 88 7/10
Using 70 is correct, since it is lowest number divisible by 5, 7 and 10.

2 * 7 and 2 * 14 are correct; other one (14/70) should be 2 * 10 = 20.
(* is now used instead of x for multiplication)

So we have:
21 35/70
35 20/70
32 28/70
======
88 83/70

83/70 = 70/70 + 13/70 = 1 + 13/70; so total becomes 89 13/70

It may be easier for you to change a fraction this way:
using 5/10; let n = numerator of new fraction:

5 / 10 = n / 70

10 * n = 5 * 70 : known as crisscross multiplication

10n = 350

n = 350 / 10 = 35 : so fraction = 35/70