Question

5см×18см= ; 100см×21см= ; 1м×18см= ; 1дм8см×5см= ; 52см×5дм2см=

Answer 1

1)90см 2)2.100см 3)1800см 4)90см 5)2704см

Answer 2

Let's solve each of these multiplication problems:

1. 5см × 18см = 90 square centimeters
2. 100см × 21см = 2100 square centimeters
3. 1м × 18см = 18 square decimeters (since 1 meter = 10 decimeters)
4. 1дм8см × 5см = 9 square decimeters (1 decimeter and 8 centimeters can be combined to 18 centimeters, which is 1.8 decimeters)
5. 52см × 5дм2см = 260 square decimeters (5 decimeters and 2 centimeters can be combined to 52 centimeters, which is 5.2 decimeters)

Remember that when multiplying two values with units, the units are also multiplied. For example, when multiplying centimeters by centimeters, the result will be in square centimeters. And when multiplying centimeters by decimeters, the result will be in square decimeters.