Answer:
x=500
Step-by-step explanation:
7/10=350/x
cross-multiply by multiplying 350 to 10 and multiply 7 to x.
example: 
7•x
350•10
7x=3500
divide both sides by 7
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x=500
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Answer:
-8.05
Step-by-step explanation:
In order to solve for C you first have to subtract 17.6 from both sides.
2c=(6/4)-17.6
6/4 is 1.5
1.5-17.6=-16.1
2c=-16.1
c=-8.05
 
        
                    
             
        
        
        
Answer:
Number of Pennies = 30
Number of Dimes = 90
Step-by-step explanation:
Let the number of pennies be p and number of dimes be d
We can write 2 equations and use substitution method to solve.
<u>Total value of all the coins is 9.30:</u>
We can write:
0.01p + 0.1d = 9.30
Note: value of penny is 0.01 and dime is 0.1, in dollars
<u>Number of dimes is 3 times number of pennies:</u>
We can write:
d = 3p
Now putting 2nd equation in first and solving for p:
0.01p + 0.1(3p) = 9.30
0.01p + 0.3p = 9.30
0.31 p = 9.30
p = 9.30 /0.31
p = 30
Now we know d = 3p, so d = 3 (30) = 90
Hence
Number of Pennies = 30
Number of Dimes = 90