Một hộp có 7 bi đỏ 3 bi vàng và 5 bi xanh. Có bao nhiêu cách lấy ra 5 viên bi mà trong đó: a, có đúng 3 bi xanh
b, có ít nhất 3 bi xanh

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

Using only odd number for numerators write two different subtraction problems that have a difference of 3/4

The stairs leading from the ground to the entrance of a plane forms a right triangle with the ground. if the distance of the stairs measures 22 feet and the ground distance measures 11 feet, how high is the entrance to the plane from the ground? which diagram represents this scenario? / 22ft © 22ft 11 ft 11 ft 22 it