Please solve this maths problem

[Islami Bhai]

i have already got the answer

[jahid89]

we know 5/9 of piece of metal has 7kg.
so in 1 peace, the mass will be= 7/(5/9)
= 63/5
now in 2/7 of the metal, the mass will be= (63/5)*(2/7)
= 18/5 = 3.6

[Islami Bhai]

good

[Altaf Sultani]

How dere u asking this qustion to me...

hw can i ans this...

did u think i'm clever?

thats funny.....

wait il try to answer

5/9 - 7
2/7 - ?

let the answer be x

therefore

5/9 - 7
2/7 - x

if u cross multiply ul get

5/9 * x = 2/7 * 7

7 gets cancelled on right side, then

5/9 *x = 2

bring 5/9 the other side, as per rule the equation will change to 9/5 when taken to the other side... therefore

x = 2 * 9/5


x = 18/5

[jahid89]

To the non math nerds, it works out to:

x = first 3 digits of phone number
y = last 4 digits

=[250(80x+1) + (2y - 250)] / 2
=[20000x + 250 + 2y - 250] / 2
=[20000x + 2y] / 2
= 10000x + y
= your phone number =)

[rainbow]

im really sorry im not a mths person, i did well in final exams but havnt done maths for past 4 years so i wouldn't be able to answer you as i cant remember how to do it.

[Islami Bhai]

Another question

find the value of r when U=22/7(r+h)
where U=33/2 and h=2

The answer is 5/2 but i m getting 13/4.
So help is needed.

[_knownothing_]

***moved to education section***

[jahid89]

13/4 is right ans bcoz
u=22/7(r+h)
u=33/2 and h=3
so r=(7/22)u-h
=13/4

[jahid89]

can anyone solve this...
if (a+b)(b+c)(c+a)=0 then prove that
(a+b)(b+c)(c+a) >= 8abc

[Islami Bhai]

Now solve this as well

if q is directly proportional to (P-1)^2 and P is always positive, find the value of P when q=80,if q=20 when P=3

[Slave-of-Allah]

the above ans is 12

[jahid89]

given that
q dpt (p-1)^2
let k is +ve constant.
q=k(p-1)^2 ....................... eq(1)

given that when q=20 when p=3
so 20=k(3-1)^2
k= 5
from eq(2) put q=80 and k=5
now
80=5(p-1)^2
16=(p-1)^2
p-1=4
p=5

[mubeen]

3.6Kg

[afzaluddin]

ya 18/5 i got tat