pri 5 tough question

Can anyone help me with this p5 maths question

thanks in advance !!!

cross multiply

I don't think primary 5 has algebra, but it's the only way I know how to solve it.

Let the total number of stamps Malvin and Ken had be X.

Initially:

(2/5)X : (3/5)X

Malvin bought 8 stamps and Ken lost 5 stamps:

(2/5)X + 8 : (3/5)X - 5

Malvin has 4/5 as many stamps as Ken:

{ (2/5)X + 8 - [ (3/5)X - 5 ] } / [ (3/5)X - 5 ] = 4/5

[ -(1/5)X + 13 ] / [ (3/5)X - 5 ] = 4/5

5 [ -(1/5)X + 13 ] = 4 [ (3/5)X - 5 ]

-X + 65 = (12/5)X - 20

X = 25

isn't total = 150?

so that initial is 60:90
then +8 and -5
68 : 85 => 4:5

I interpreted the 4/5 as many stamps as Ken to be 80% more stamps as Ken.

*shrugs*

If 4/5 means 4:5 then,

Let X be the initial total and Y be the final total.

(2/5)X + 8 = (4/9)Y --------(1)

(3/5)X - 5 = (5/9)Y ---------(2)

Solve for X and Y.

X = 150

Y = 153

Don't know how to use diagrams like that to solve, was never taught the technique.

If 4/5 means 4:5 then,