Question 939903
Q1 .A rectangular piece of land measures {{{L=0.8dm}}} by {{{W=.5dm}}} 

it is to be fenced with {{{four}}} lines of wire 
the length of wire that is needed is equal {{{four}}} times the perimeter of a rectangular piece of land

if  land measures {{{L=0.8dm}}} by {{{W=.5dm}}}, perimeter is {{{P=2(0.8dm+0.5dm)}}}
{{{P=2(1.3dm)}}}
{{{P=2.6dm}}}

{{{four}}} times the perimeter is:{{{4*2.6dm=10.4dm}}}-the length of wire that is needed 


Q2. A rectangular garden is {{{105m}}} by {{{75m}}}. 

how many round of this garden will a boy make, if he runs {{{3600m}}} 

divide {{{3600m}}} by  perimeter

{{{P=2(105m+75m)}}}

{{{P=2(180m)}}}

{{{P=360m}}}

{{{360cross(0)cross(m)/36cross(0)cross(m)=360/36=10}}} 

 a boy will make {{{10}}} rounds 


Q3. Find the perimeter of square equal in area to two squares whose sides are {{{12m}}} and {{{5m}}} respectively.

We know perimeter of square {{{A= 4(side)}}}

So side of first square is {{{ 12m}}} and area is {{{ 12m*12m=144m^2}}} 
Side of second square  is {{{5m}}}and area is {{{ 5m*5m=25m^2}}} 

the area of both is  {{{  144+25=169m^2}}}

Area of third square  is equal to the area of both squares above, so,the area of third square  is {{{  169m^2}}}


So side of third square = {{{13m}}} [because {{{13m*13m=169m^2}}}]

{{{Perimeter = 4*Side = 4*13m = 52m}}}