Question

6cm diameter discs are cut from a sheet 130cm long and 70cm wide.(a)How many discs can be cut in this way (b) what area of the sheet is wasted?
(My working so far).
Area of rectangle=L*B
130*70=9100cm^2
area of circle=22/7 *(6/2)^2=28.286cm^2
(a)no of discs cut=9100/28.286=321
pls help with the (b) part of the question.which is: what area of the sheet is wasted?

Answer 1

just subtract what was used from the original amount:

9100 - 321*28.286

However, that assumes that all the leftover parts could be combined to form new circles; not very likely. A better way to look at it is to decide how many rows and columns of discs could be cut.

130/6 = 21.67
70/6 = 11.67
So, you have 21 rows of 11 discs, or 231 discs

Now the wastage is 9100 - 231*28.286

In fact, however, there are better ways of packing the discs onto the sheet than a square lattice, but that gets quite complicated.

Answer 2

248 322.794

Answer 3

I m not satisfied with the answers.

Answer 4

Am not satisfied with the answers

Answer 5

Answer to the second question B

Answer 6

Explain as if you teach a SS1 child it’s hard to comprehend

Answer 7

Wrong answer