4

The snail reaches the top of the pit on the 16th day!
On the first day, the snail reaches a height of 5 meters and slides down 4 meters at night, and thus ends at a height of 1 meter.
On the second day, he reaches 6 meters, but slides back to 2 meters.
On the third day, he reaches 7 meters, but slides back to 3 meters.
...

A decimal point (5.6)

6 years old
1+2+3+4+5+6=21

96 km/h
Let the length of the journey be n km. The first half of the journey takes (1/2×n)/80 = 1/160×n hours, and the second half of the journey takes (1/2×n)/120 = 1/240×n hours. The average speed for the complete journey is n/(1/160×n+1/240×n) = 96 km/h.

Yes: 1+1+5+13=20

Answered A, B and C or 40, 27 and 85 is correct.

1, 2 and 3

3. Take the fraction and round up to get both 3 and 4

98¹ - 2 = 96

9

1. 6 % 2 x 3
2. 3 x 3
3. 9

They are equal
36 % of 67 = 36 x 67 / 100 = 24, 12
67 % of 36 = 67 x 36 / 100 = 24, 12