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IGCSE MATHS DOUBTS HERE !!!!
HUSH1994:
what are ALL the matrix transformations i need for IGCSE?including all reflections,rotation,translation,shear,stretch,enlargement?Please??
Vin:
--- Quote from: HUSH1994 on October 06, 2010, 02:49:52 pm ---what are ALL the matrix transformations i need for IGCSE?including all reflections,rotation,translation,shear,stretch,enlargement?Please??
--- End quote ---
https://studentforums.biz/math-147/transformation-martices-igcse/msg167877/#msg167877
WARRIOR:
1.The population of an island increases by 10% each year.After how many years will the original population be doubled.
2.A bank pays interest of 11% on 6000 in a deposit account..After how many years will the money have trebled
3.A tree grows in height by 21% per year. It is 2m tall after one year. After how many more years will the tree be over 20m tall?
thx in advanced.
elemis:
Let the initial population be 100 and the number of years after which the population doubles let it be n.
100 * 1.10n = 200
Solving for n give : 1.10n = 2
Hence, log 2 / log 1.1 = 7.27 years (3 s.f.)
Therefore answer is 8 years. Since after 7.27 years there will only be 199.9 people.
WARRIOR:
--- Quote from: Ari Ben Canaan on October 15, 2010, 07:05:55 am ---Let the initial population be 100 and the number of years after which the population doubles let it be n.
100 * 1.10n = 200
Solving for n give : 1.10n = 2
Hence, log 2 / log 1.1 = 7.27 years (3 s.f.)
Therefore answer is 8 years. Since after 7.27 years there will only be 199.9 people.
3. The answer at the end n = 12.1 , and so 1.21^12.1 x 2= 20m exactly
why is the asnwer in the book 13?
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ok but for the next one , the answer in my book says 12 years why?
6000 x 1.11^n = 18000
1.11^n= 3
thergfore log 3/ log 1.11
=10.5
and anywy the anwer in the book says 12 and 6000 x 1.11^12 = 20000 +
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