Problem Solving (PS) | Re: In town A, the price of tea is defined by the expression $(100 + 0.10n

T = (100+0.1n)
C = (89+0.15n)

T = (10000+10n)/100
C = (8900+15n)/100

let's try n at 100

T = 11000/100 = 110 (Max value of Tea)
C = 10400/100 = 104
Let's try n at 120
C = 10700/100 = 107
For every 20 days increase, C price increases by 3$
Then at n = 140
C = 11000/100 = 110

As the given year is not a leap year (n = 365)
Jan = 31
Feb = 28
Mar = 31
Apr = 30
May = 31
J+F+M+A+M = 151
-10 days in May as we need 140 days, i.e, May 20th

C is the answer.

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