So...
1,980,000 eats oranges
990,000 eats apples
30,000 don't know (most probably they like bananas)
128,700 apple 'preachers'
257,400 'converts'
of which you could have (at extremes)
all those who were converted ate oranges
257,400 (orange->apple)
AND
all those who don't know converted, as well as the balance of orange eaters.
30,000 (don't know->apple) 227,400 (orange->apple)
so you would end up with anything from
57.42% to 58.42% who still eat oranges
If you want a single answer, I'd say 57.92%
3 000 000 chilldren
66% like to eat orange
33% like to eat apple
1% dun know
If 13% of the 33% who like apple convince 2 more friends to eat apple for a change. How many percentage of the children eat orange?