## anonymous one year ago Working at a constant rate, Bob can produce x/3 widgets in 8 minutes. Working at a constant rate, Jack can produce 2x widgets in 40 minutes, where x>0. Which of the following is greater: a. The number of minutes it will take Bob to produce 5x widgets. b. The number of minutes it will take Jack to produce 6x widgets.

1. anikhalder

Can you say how many minutes Jack will take to produce x widgets?

2. anonymous

8?

3. anikhalder

Time taken by Jack to produce 2x widgets = 40 minutes Hence, time taken by Jack to produce x widgets = ?

4. anonymous

?

5. anonymous

they're equal?

6. anonymous

2 minutes for both?

7. anikhalder

If you can make 20 objects in 40 minutes, how long will it take for you to make 1 object?

8. anonymous

1/2

9. anonymous

2 inutes

10. anonymous

minutes

11. anikhalder

how did you calculate that?

12. anonymous

20/40 = 2/4 = 1/2 = 1 object every 2 minutes

13. anikhalder

okay so if Jack makes 2x objects in 40 minutes, how long will it take for him to make 1 object?

14. anonymous

|dw:1437682608642:dw|

15. anikhalder

Perfect!

16. anonymous

|dw:1437682660689:dw|

17. anikhalder

No. Suppose you make 1 object in 2 minutes. How long will you take to make 5 objects?

18. anonymous

10 minutes

19. anikhalder

Yes! So if Jack makes x objects in 20 minutes How long will it take for him to make 5x objects?

20. anikhalder

Sorry, 6x objects I meant

21. anonymous

4 minutes?

22. anikhalder

If he makes x objects in 20 minutes Then how can he possibly make 6 times the number of objects that he took 20 minutes to make, in 4 minutes?

23. anonymous

oh then is it 100?

24. anikhalder

for 5x it is 100 for 6x it is 120

25. anonymous

26. anikhalder

Okay treat the question like this: I make 1 object in 24 minutes On the other hand, you take 20 minutes to make the same object. Then tell me now, How long will I take to make 5 such objects? How long will you take to make 6 such objects?

27. anonymous

|dw:1437683549742:dw|

28. anonymous

29. anikhalder

|dw:1437683586813:dw|

30. anikhalder

5 x 24 = 120

31. anonymous

oops

32. anikhalder

In this case, it's like a variable, for example: Let's take x = 1 , and replace the x with 1 and read the question once again: Working at a constant rate, Bob can produce 1/3 widgets in 8 minutes. Working at a constant rate, Jack can produce 2 widgets in 40 minutes, where 1>0. Which of the following is greater: a. The number of minutes it will take Bob to produce 5 widgets. b. The number of minutes it will take Jack to produce 6 widgets.

33. anikhalder

Or if you want take x = 2 or x = 3 or 4 or so on, it's an alphabet which you can replace with positive numbers

34. anonymous

hmmmm ook

35. anikhalder

|dw:1437684144772:dw|

36. anonymous

y r they both 120

37. anikhalder

PLEASE NOTE: Here x is not equal to 24 or 20 It means the time taken by Bob to make x objects is 24 minutes and the time taken by Jack to make x objects is 20 minutes

38. anonymous

hmmmm ok...

39. anikhalder

40. anonymous

got it thanks u

41. anikhalder