4.
Scales are ratios.
In this question, the scale is 0.5 cm:1 m.
This means that every 0.5 cm in the scale drawing is equal to 1 m in the real thing.
If the length of the bedroom in real life, not in the scale drawing, is 4.5 m, then you can put this on the meters side then solve for cm.
This would be x cm:4.5 m.
To find how many cm the length of the scale drawing is for Asia's bedroom, divide 4.5 by 1.
Since the ratios must be equivalent and equal to be true, whatever was done to get from 1 m to 4.5 m must be done to 0.5 cm to get the value of x.
4.5 / 1 = 4.5
Now multiply 0.5 by 4.5 to get x.
0.5 • 4.5 = 2.25
x = 2.25
2.25 cm:4.5 m is the ratio of the measurement on the scale drawing to the actual length of the bedroom.
This means the answer is A. 2.25 cm.
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5.
In order to answer this question, we must first interpret its meaning.
This is saying that the actual distance between the plates is 90 feet and that the distance between them on Alvin's scale drawing is 2.5 inches.
Before we can find the answer, we must convert feet to inches.
1 foot = 12 inches
90 feet = 1080 inches
So in terms of a ratio of the scale drawing measurements to actual distance, the scale is 2.5 in:1080 in.
Now we must simplify this ratio.
This can be done by dividing both sides by 2.5 in, which is the GCF of both sides.
2.5 / 2.5 = 1
1080 / 2.5 = 432
So the scale is 1 in:432 in.
To find the final answer, just convert the 432 inches back to feet.
12 inches = 1 foot
432 inches = 36 feet
This means the scale is 1 inch:36 feet.
So the answer is D. 1 in = 36 ft.
Hope this helps!