Discrete domains and continuous domains are both sets. However a discrete domain contains a finite number of elements and continuous can contain and infinite number of elements.
To find how long it would take him, one has to divide 400 by 160 and then multiply 5 by what that number is. You multiply 5 by the quotient because that is the number that would make it proportional. 400/160 x 5 is 12.5, meaning that the answer is 12.5 minutes, or A.
To find the area, move each semicircle to fill up the square, you'll see there are three squares, each with an area of 4*4=16, so the total area is 3*16=48
Now the perimeter:
the perimeter of a circle is π times the diameter.
perimeter of each semicircle: (1/2)π*4=2π
there are altogether 6 arches and two straight sides, so the total is
2π*6+4*2=12π+8
the area is 48 square units, the perimeter is 12π+8 units.
Let us check series : -10 /-2 = 5 -50/-10 = 5
so it is a geometric series with a= -2 and r= 5
sum formula for n terms of geometric series = a ( r^n -1 ) /( r-1)
here we find S5 that is n= 5 = -2 ( 5^ 5 - 1) /( 5-1)
= -2 ( 3125 -1) / 4 = -1562
second series is : 1.5/1 = 1.5 2.25/1.5 = 1.5
this is also geometric series but n = 12 a= 1 and r= 1.5
we use same formula
S12 = 1 ( (1.5) ^12 -1) /( 1.5-1) =
128.74 / 0.5 = 257.49
Last is 2/1= 2 4/2 = 2 8/4 = 2 so r = 2 a = 1 and n = 12
we use same formula 1 ( 2^12 - 1) / (2-1)
= 4095
Answers : -1562 , 257.49 , 4095