I have 3 straight sides. What am I?
Triangle

Cylinder
What is one more than 17?
18
What is one less than 2?
1
What number has 1 set of 10 and 7 further ones?
17
I have one curved side. What am I?
19+0=
Cube
What is one more than 12?
13
What is one less than 8?
7
What number has one set of 10 and 5 further ones?
15
I have 4 straight sides. All sides are of equal length. What am I?
square

Cone
What is one more than 2?
3
What is one less than 18?
17
What number has one set of 10 and 2 further ones?
12
I have 6 straight sides. What am I?
I am shaped like a ball. What am I?
Sphere
What is one more than 9?
What is one less than 11?
10
What number has one set of 10 and 9 further ones?
19
3D Shape
What is one more than 15?
16
What is one less than 20?
19
What number has two sets of 10 and 0 further ones?
20