xXmuffin0manXx
cera
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- 2010
Okay. I've forgotton how to do this one...
i) The average of 8 numbers is 15. When a 9th number is added, the average becomes 12. What is the 9th number.
And now for something a little harder..
ii)Write an expression for n
(1+ 1/2)(1+ 1/3)(1+ 1/4)...(1+ 1/n)
iii) A semicircle with points A, B, C, D all lie on the diameter and are equidistant. A and D both lie on the circumference.
(this is where you draw a diagram and label points A, B, C, D on the diamater and making sure they are equidistant A through to D)
Within the semicircle AD, a semicircle AB is drawn such that it takes away the part of the semicircle AD.
(So on AB, you draw a semicle that is corresponding with the larger semi circl)
The same is done for BD.
(So in a way, you get like a retarded umbrella without the handle)
What is the ratio of the new shape and the original semicircle AD?
_________
Thanks
i) The average of 8 numbers is 15. When a 9th number is added, the average becomes 12. What is the 9th number.
And now for something a little harder..
ii)Write an expression for n
(1+ 1/2)(1+ 1/3)(1+ 1/4)...(1+ 1/n)
iii) A semicircle with points A, B, C, D all lie on the diameter and are equidistant. A and D both lie on the circumference.
(this is where you draw a diagram and label points A, B, C, D on the diamater and making sure they are equidistant A through to D)
Within the semicircle AD, a semicircle AB is drawn such that it takes away the part of the semicircle AD.
(So on AB, you draw a semicle that is corresponding with the larger semi circl)
The same is done for BD.
(So in a way, you get like a retarded umbrella without the handle)
What is the ratio of the new shape and the original semicircle AD?
_________
Thanks