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On a photograph a person stood next to a rock is 5.8 cm high and the rock was 3.8 cm across.
Assuming the person is 17 m tall what is the actual width of the rock?
Can you show working please.
2007-09-09 07:13:59 · 3 answers · asked by Rachel 1 in Science & Mathematics ➔ Mathematics
Im sure you mean 1.7. a 17 meter tall person would be over 50 ft tall:
use a proportion:
height/width = height2/width2
5.8/3.8 =1.7/X
X=3.8*1.7/5.8
X=1.113 meters wide
2007-09-09 07:27:17 · answer #1 · answered by bignose68 4 · 0⤊ 0⤋
A photograph is a scaled-down representation of real life. All the distances are reduced by the same factor.
If a 5.8 cm distance represents a real life distance of 17 m, find the scale factor needed to convert them. Apply that same scale factor to 3.8 cm to get the real life distance in meters that represents the rock's width.
2007-09-09 14:22:00 · answer #2 · answered by Anand S 3 · 0⤊ 0⤋
This is a ratios question, I have never seen a 17m person, perhaps it was 1.7 m
W = rock width
W / 3.8 = 17 / 5.8
OR
W / 3.8 = 1.7 / 5.8
whichever applies, in either case solve for W by multilying both sides of the equation by 3.8 to get:
W= 17 * 3.8 /5.8 = 11.14 m
OR
W= 1.7 * 3.8 /5.8 = 1.11 m which is a more realistic answer.
2007-09-09 14:27:35 · answer #3 · answered by 037 G 6 · 0⤊ 0⤋