Answer:
Anywhere from 446 to 454 children.
446 rounded to nearest ten is 450.
447 rounded to nearest ten is 450.
448 rounded to nearest ten is 450.
449 rounded to nearest ten is 450.
450 rounded to nearest ten is 450.
451 rounded to nearest ten is 450.
452 rounded to nearest ten is 450.
453 rounded to nearest ten is 450.
454 rounded to nearest ten is 450.
So the answer is 446 - 454 children. Hope it helps!