1: the perimeter of a circle is 15,7 dm. Its's area is...cm2
2: the ratio of the number of girls to the number of boys in a classroom is 5:4. When 10 girls left the classroom, the ratio of the number of boys to the number of girls became 4:3. How many students were in the classroom at first?
3: 47/250 dm3=...cm3
4: At the party 60% of the boys are dancing with 80% of the girls. How many people are dancing if there are 35 people ( A pair cludes only one boy and one girl)
5: An aquarium is 8dm deep, 12 dm long and 0,3 m wide. What is the volume of the aquarium in cubic centimeter?. Answer: the volume of the aquarium is...cm3
