1 file + 3 pens = $32.85 --------------- (1)
2 files + 8 pens = $83.50 ----------------(2)
(1) x 2 :
2 files + 6 pens = $65.70 ----------------(1a)
(2) - (1a) :
2 pens = $17.80
1 pen = $8.90
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Answer: One pen costs $8.90.
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Consider the function f ( x ) = 2479 ⋅ 0.9948x First compare this with f ( x ) po ( 1 + r ) ^ 2 We get po = 2479 And 1 + r = 0.9948 = 1 – 0.0052 r = -0.0052 < 0 Therefore, f is an exponential decay function with a decay rate of 0.0052 x 100 = 0.52%
(1/3)t = (2/3)c, where "t" is for teapot and "c" is for the container.
Multiply both sides by (3/2) in order to get 1 on the right-hand side.
(3/2)(1/3)t = (3/2)(2/3)C
simplify the equation to get the answer which is:
(1/2) teacup = 1 full container.
Hope this helps :)
