Can some one help me, l forgot how to do it

48 cm² and 28 cm

Step-by-step explanation:

The ratio of the sides 1 : 2 = 4 : 7

The ratio of the sides 2 : 1 = 7 : 4

The ratio of perimeters is the same as ratio of sides

let the perimeter of 2 be x , then

= ( cross- multiply )

4x = 112 ( divide both sides by 4 )

x = 28

Perimeter of fig. 2 is 28 cm

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Given ratio of sides = a : b , then

ratio of areas = a² : b²

Here ratio of sides = 4 : 7

ratio of areas = 4² : 7² = 16 : 49

let x be the area of fig. 1 and using proportion

= ( cross- multiply )

49x = 2352 ( divide both sides by 49 )

x = 48

area of fig. 1 is 48 cm²

1. 3.4/4

2. 0.8/7

3. 0.5 x 3

4. 0.9 x 6

5. 10.8

6. 2.35

7. 0.567

8. 9.35

9. 0.02

10. 0.06

11. 0.16

12. 0.42

13. 0.63

14. 5.6

15. 8.1

16. 9.9

17. 0.28

18. 0.48

19. 0.27

20. 0.49

21. 0.45

22. 0.72

23. 0.9

24. 0.88

25. 0.75

26. 0.16

27. 0.328

28. 0.495

29. 0.72

30. 1.068