Answer:
42:21 as a ratio
Step-by-step explanation:
The way you would make this a ratio was to make inches to inches so it would be 42:21.
 
        
             
        
        
        
Given: 
The number of teeth = t = 25
The gear is driven by a 10-tooth driver gear (T) at 250 RPM
Let the speed = s
So, using the ratio and proportion

Solve for s:

So, the fear will be driven by 625 RP
 
        
             
        
        
        
<span><span>9<span>(6j+2+j)</span></span><span>9<span>(6j+2+j)</span></span></span>Add <span><span>6j</span><span>6j</span></span> and <span>jj</span> to get <span><span>7j</span><span>7j</span></span>.<span><span>9<span>(7j+2)</span></span><span>9<span>(7j+2)</span></span></span>Apply the distributive property.<span><span>9<span>(7j)</span>+9⋅2</span><span>9<span>(7j)</span>+9⋅2</span></span>Multiply <span>77</span> by <span>99</span> to get <span>6363</span>.<span><span>63j+9⋅2</span><span>63j+9⋅2</span></span>Multiply <span>99</span> by <span>22</span> to get <span>1818</span>.<span>63j+<span>18</span></span>
        
             
        
        
        
Multiply the first digit by 3 then subtract the answer by 2.  Rule:  x 3  - 2