18+15-10 =13 (person)

40- 13=27 (person)

A: So there are 27 people who don't participate in both groups.

The second question:

45-29= 16 (person)

16-( 10-3)=9 (person)

A: Then nine people got full marks in Chinese.

The third question:

The multiple of 4 is: 50÷4= 12, so there is 12.

The multiple of 6 is: 50÷6=8, so there is 8,

The multiple of 4 and 6 is: 50÷ 12=4, so there is 4.

So you can get: now there are students facing the teacher:

50- 12-8+4=34

The fourth question:

Each 100, 1, 100.

Multiply by 2 and send another (equal to 2) 50.

Multiplied by 3, there are 66 cyclic branches (equal to 3 branches).

Multiply by 6 and send another one (repeated prize) 16.

50+66+ 16= 132 (branch)

A: So, the club has prepared 132 prize pencils for this activity.

The fifth question:

Mark every 3 cm, that is, every 4 cm. A * * * system 180÷4=45 (pieces)

Similarly, mark 5 cm, and * * is 180÷5=36 (pieces).

Twice * * * made 36+45=8 1 (piece)

However, 4 cm and 5 cm have overlapping points, such as 20 cm, that is, the common multiple of 4 and 5, that is, the multiple of 20, * * * has 180÷20=9 (pieces).

8 1-9=72 (paragraph)

A: The rope was cut into 72 sections.

I hope these can help ruby Baby 234.

O(∩_∩)O~！