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:
B
Step-by-step explanation:
The height to height ratio of the 2 rectangles = 21 : 7 = 3 : 1, that is
The sides of the red rectangle are one third of the corresponding sides in the blue rectangle, thus
w = 34 ÷ 3 ≈ 11.33 ( to 2 dec. places ) → B
Simplified form would be twentieth root of 6
