Answer:
64.3 lumens
Step-by-step explanation:
Data provided in the question:
Length of the testing chamber = 35 cm
Light at one end = 10 lumens
Light at other end = 200 lumens
now,
since the variation is linear,
therefore, the gradient of the variation
=
= 5.43
also,
the darkest end is the end with 10 lumens
therefore,
The lumens at 10 cm from the darkest end
= 10 + 5.43(10)
= 10 + 54.3
= 64.3 lumens
9514 1404 393
Answer:
BC ≈ 17.0 (neither Crow nor Toad is correct)
Step-by-step explanation:
The left-side ratio of (2+4)/4 = 3/2 suggests BC is 3/2 times the length DE. If that were the case, BC = (3/2)(11) = 16.5, as Crow says.
The right-side ratio of (5+9)/9 = 14/9 suggests that BC 9 is 14/9 times the length DE. If that were the case, BC = (14/9)(11) = 154/9 = 17 1/9 ≈ 17.1, as Toad says.
The different ratios of the two sides (3/2 vs 14/9) tell you that the triangles are NOT similar, so the length of BC cannot be found by referring to the ratios of the given sides.
Rather, the Law of Cosines must be invoked, first to find angle A (109.471°), then to use that angle to compute the length of BC given the side lengths AB and AC. That computation gives BC ≈ 16.971. (See the second attachment.)
