Answer:
21 is 20% of 105
Step-by-step explanation:
20% * x = 21 
20/100 * x = 21 
x = 21 * 100/20 
x = 105
If you are using a calculator, simply enter 21×100÷20, which will give you the answer.
 
        
                    
             
        
        
        
First I'm going to go through the choices with you and evaluate 
each one.  Then after that, I'm going to hand you a secret that 
I promise is going to knock your socks off.
a- Calculate the ratio of the diameter to the radius for each circle 
and show that they are equal. 
-- That won't tell you anything. The ratio of the diameter 
to the radius of EVERY circle is 2 .
b- Calculate the ratio of degrees to the circumference for each circle 
and show that they are equal.
-- That doesn't tell you anything.  The circumference 
of EVERY circle subtends a central angle of 360°. 
c- Calculate the ratio of the área to the circumference for each circle 
and show that they are equal. 
-- That doesn't tell you anything.  The ratio of the area 
to the circumference of EVERY circle is (radius/2).  
They're only equal if the circles are the same size. 
d- Calculate the ratio of the diameter to the circumference for each circle
and show that they are equal.
-- That doesn't tell you anything.  The ratio of the diameter 
to the circumference of EVERY circle is  1/pi.   If the ratio isn't 
1/pi, then you're not looking at a circle.  
None of these choices tells you whether the two circles are similar.
What are you going to do ?  How can you tell ? ?
Here's the surprise I promised you.
Beware of flying socks:
All circles are similar to all other circles.
Good night.
        
             
        
        
        
Answer:
176 
Step-by-step explanation:
140.8/0.8=176
Hope it helps
 
        
             
        
        
        
1.)    50 - 14 = 4x
x = 50 - 14 divided by 4 = 36/4 = 9. 
                    x = 9
2.)     6(3x) -12 + 5x = 57
           18x + 5x = 57 + 12
               23x=69
                  x = 69 divided 23 = 3
                       x = 3