total flowers: 40u
red flowers: 8u
yellow flowers: 32u

after sale, left
red flowers: u
yellow flowers: 32u-255
total flowers: 16u

u + 32u - 255 = 16u
u = 15

sold 24x15 = 360 flowers


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Thank u

Sorry how did u get the total units for total flowers before sale

the value of 40 units is chosen out of convenience & easy workings.

why?

in the qn, for red flowers,
the fractions " 1/5 " & " 7/8 " appear.

5x8 = 40

in this way, the workings would not contain fractions of units and complicate things.

u can always choose other value for total flowers. the method remains the same, but u would see " fractions of units ". AND u might make careless mistakes along the way.

see alternative ans below:
[ note: this is for illustration purposes]

total flowers: 10u
red flowers: 2u
yellow flowers: 8u

after sale, left
red flowers: u/4 [<= " fractions of units " ]
yellow flowers: 8u-255
total flowers: 2/5 x 10u = 4u

u/4 + 8u - 255 = 4u
u/4 + 8u - 4u = 255
u = 60

sold 6x60 = 360 flowers


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