equal fraction concept
step 1: find the equal fraction
"After she sold 2/5 of the roses and 3/4 of the sunflowers, she had an equal number of roses and sunflowers left."
roses sold → 2/5 roses left → 1 - 2/5 = 3/5
sunflowers sold → 3/4 sunflowers left → 1/4
3/5 roses = 1/4 sunflowers
step 2: make numerators the same
3/5 roses = 3/12 sunflowers
step 3: convert to units
total roses → 5u total sunflowers → 12u
difference (units) → 12u - 5u = 7u
difference → 504
7u → 504 1u → 504 ÷ 7 = 72
total units → 12 + 5 = 17u
17u → 17 x 72 = 1224