+0  
 
0
134
3
avatar

https://vle.mathswatch.co.uk/images/questions/question17968.png

 

https://vle.mathswatch.co.uk/images/questions/question17362.png

 Mar 31, 2020
 #1
avatar+112421 
+2

First  one

 

Blue  area =  area of large rectangle  - area of  smaller rectangle  = (21)(42)  - (15)(28)   = 

 

882  -  420   =

 

462  cm^2

 

 

Second  one

 

Assume  that  the log  =16m  =  1600  cm

Assume  that each fence post =  65 cm

 

So......the largest number of fence posts  that  can be  cut  from the log =  1600/65  =  24

 

 

cool cool cool

 Mar 31, 2020
 #2
avatar
0

the first one it says its wrong

 Mar 31, 2020
 #3
avatar+112421 
+1

Ah....I didn't  notice  the "to  the  nearest cm"  thing

 

Let  the inner dimensions  be    14.5  x  27.5

 

And let the outside  dimensions   be as shown

 

The  max  for the blue  area is   (21) (42)  -  ( 14.5)(27.5)  =   882  - 398.75  =   483.25 cm^2

 

 

cool cool cool

CPhill  Mar 31, 2020

38 Online Users

avatar