Algebra Again?

Question

If a-2b / b = 5/10
Find a+b / b and a / b

Answer 1

from the first eqn, we know b = 10.

so analyzing the numerator: a - 2b = 5
but we know b = 10: a - 2*10 = 5
a -20 = 5
a = 25.

Plugging these into the eqns:
(a+b)/b = (25+10)/10 = 35/10 = 7/2

and

a/b = 25/10 = 5/2

Answer 2

Firstly, we cannot assume that b = 10.

We can simplify this by saying: a-2b/b = 1/2
Cross multiplying gives us : b = 2a-4b or: 2a = 5b
So a = 5b/2 and b = 2a/5 or a = 2.5b and b = a/2.5

Substituting each one at a time gives the answer of 1/2 in both cases. Which shows this to be true.

So we have : 2.5b+b/b which is 3.5b/5 = 3.5 for the first equation.

In the second case we have 2.5b/b = 2.5

Answer 3

a/b=5/2 and a+b/2=7/2

Answer 4

(a+b)/b - (a-2b)/b = (3b)/b = 3

So (a+b)/b = (a-2b)/b + 3 = 5/10 + 3 = 35/10

(a/b) = (a+b)/b - b/b = (a+b)/b - 1 = 35/10 - 1 = 25/10

Answer 5

(a-2b)/b = 5/10
10(a-2b) = 5b
10a-20b = 5b
10a = 25b
a/b = 25/10
a/b = 5/2
a/b = 2.5

(a+b)/b
= (a/b) + (b/b)
= (a/b) + 1
= 2.5 + 1
= 3.5

Answer 6

42

Answer 7

miggity got the right answer for the wrong reason - assuming b=10 was wrong

Answer 8

[a -2b ]/b = 5/10
[a -2b ]/b = 0.5
a -2b =0.5b
a =2b + 0.5b
a = 2.5b

[a +b]/b = [2.5b +b]/b ..............put a=2.5b
=3.5b/b
=3.5

a/b = 2.5b/b ............. put a = 2.5b
= 2.5

Answer 9

http://consoles.real-incentives.com/?referral=25503

Answer 10

(a-2b)10=5b
10a-20b=5b
a=25b/10=2.5b

(a+b)/b=(2.5b+b)/b=3.5
a/b= 2.5b/b=2.5
verefy:
(2.5b-2b)/b=0.5
yes