_ :21=5:7 10:100=_:200

12:28=_:7

48:_=8:9

36:75=12:_

56:120=_:8

2:4=_:2

45:_=15:20

_:65=9:13

180:210=_:35

63:_=7:8

48:72=4:_

_:100=6:10

36:108=6:_

3:_=1:3

_:180=8:20

81:126=9:_

_:33=2:3

Step-by-step explanation:

1) 10:18=5:9

2) 15:21=5:7

3) 10:100=20:200

4) 12:28=3:7

5) 48:54=8:9

6) 36:75=12:25

7) 56:120=3.733:8

8) 18:24=6:8

9) 2:4=1:2

10) 45:60=15:20

11) 45:65=9:13

12) 180:210=30:35

13) 63:72=7:8

14) 48:72=4:6

15) 60:100=6:10

16) 36:108=6:18

17) 3:9=1:3

18) 72:180=8:20

19) 81:126=9:14

20) 22:33=2:3

1. 15 :21=5:7

2. 10:100=20:200

3. 12:28=3:7

4. 48:54=8:9

5. 36:75=12:25

6. 56:120=3.73..:8

7. 2:4=1:2

8. 45:60=15:20

9. 45:65=9:13

10. 180:210=30:35

11. 63:72=7:8

12. 48:72=4:6

13. 60:100=6:10

14. 36:108=6:18

15. 3:9=1:3

16. 72:180=8:20

17. 81:126=9:14

18. 22:33=2:3

answer rather than having to add and subtract the measurements of the semi-circle, notice that the semicircle to the left of ad is actually identical in area to the blank semicircle-shaped space to the left of bc. so if we transferred the red semicircle into the blank space, we would end up with a square of side length 24 cm. the area of a square is s^2 = 24^2 = 676 cm^2.

u also answered this so i think u would know but i am here to

put in or use mine