Write "st div. by 6r" as
  st
-------
   6r
                                                                                   45s        15s        3s
If r =5 and t = 45, but s is unknown, then we get    --------- = --------- = -------
                                                                                    6(r)        2(5)        2
        
             
        
        
        
Use b for bicycles b and t for tricycles.
We know that each bicycle has 2 wheels, and each tricycle has 3 wheels, and if the entire number of wheels is 57, that means the 
equation would be: 2b + 3t = 57
We can "separate" b by calling it "25 - t" as an alternative, 
2(25 - t) + 3t = 57, or
50 - 2t + 3t = 57,
or 50 + t = 57, so
t = 7 So there must be 18 bicycles and 7 tricycles.
CHECKING:You can check this out by multiplying 7 tricycles x 3 wheels, which is 21,
and 18 bicycles x 2 wheels, which is 36
36 + 21 = 57
        
             
        
        
        
Answer:

Step-by-step explanation:
- -1/9 × -5/4: 9 × 4 = 36, -1 × -5 = 5
- Put them together: 5/36
 
        
                    
             
        
        
        
Answer:
The simplified form of  is
 is 
Step-by-step explanation:
Given : 
We have to write the simplified form of 
Consider the given expression 
We know 
and 
Thus, 

Simplify, we have, 

Thus, The simplified form of  is
 is 