100 = 2t + 4f
40= t + f
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get t or f by itself first.
f = 40 - t : Then substitute it back into for f in the other equation
100 = 2t + 4f
100= 2t +4(40-t)
100= 2t + 160 - 4t
100 = -2t + 160
-160 -160
<u>-60 </u>= <u>-2t
</u>-2 -2
t = 30 (Then plug this into either equation to solve for f)
Therefore,
t = 30 questions
f = 10 questions
Answer:
D. 
Step-by-step explanation:
The given expression is;
This is the same as;
The denominators are the same.
Subtract the numerators and write one denominator;
Rewrite to get;
75% ended the race
25-18=6
6 goes into 24 4 times so it is 25% that did not finish
100%-25%=75%
So 75% finished the race
Answer:
The prime factors of 693 are 3, 7, 11.
Hope this helps!
