+0

0
280
5

remaining amount of money Adam had to the amount of money that Firdaus

to the remaining amount of money that Firdaus had would become 7:11. How

much money did Adam and Firdaus have altogether at first?

Feb 17, 2022

#1
+1

Call the amount that Friday  had originaly = F

We  have these two  equations

(A - 9) / F  =   2/7

A / ( F - 9)  =  7/11

Cross-multiply in each case

7 (A - 9)  = 2F

11A  = 7 (F - 9)                 simplify  both

7A  - 63   = 2F                      (1)

11A =  7F - 63                  rearrange  both as

7A - 2F  =  63

11A - 7F  = - 63            multiply  the first equation by -7   and the second by 2

-49A  + 14F  = -441

22A  -   14F  =  -126           add these

-27A  = -567

A = -567 / -27   =   21     ( Adam originally had \$21  )

And using (1)  to find F

7(21)  - 63  =  2F

147 - 63  =  2F

84  = 2F

84/2   = F =   42    (   Friday originally had \$42 )

They originally had  \$63  dollars combined   Feb 17, 2022
#2
0

It is supposed to be called Firdaus

tacoBRO1023  Feb 17, 2022
#4
0

Yo, Taco....starts out as 'Friday'    then morphs to 'Firdaus' .....

ElectricPavlov  Feb 18, 2022
#3
+1

(a-9) / f = 2/7          f = 7/2 (a-9)

a / (f-9) = 7/11        f = 11/7 a + 9      equate the two 'f's

7/2 ( a - 9 ) = 11/7 a + 9

1  13/14  a = 40.5

a = 21           then you can easily solve for f  = 7/2 ( a-9) = 42 dollars

Feb 18, 2022
#5
+1

Firdaus = \$y

(x - 9)/y = 2/7 -(1)

2y = 7(x - 9) = -(1)

2y = 7x - 63 -(1)

x/(y - 9) = 7/11

11x = 7(y - 9)

11x = 7y - 63

2 (11x - 7y = -63)

7 (2y - 7x = -63)

14y - 49x = -63 * 7

22x - 14y = -63 * 2

| - - - - - - - - - - - - - - - - - -
|       -27x = -567
|            x = 21
|            y = 42
|   x + y = \$63
|
|
|

Feb 20, 2022