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Primary 5
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Number and Algebra
Another one. Pls help!
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3
Kai Meng
Analyze it based on odd and even stages.
When the Stage # is odd:
White: #^2
Black: (#-1)^2
When the Stage # is even:
White: (#-1)^2
Black: #^2
At Stage 10, 10 is even, so
White: (10-1)^2 = 9^2 = 81.
At Stage 99, 99 is odd,
White: 99^2 = 9801
Black: (99-1)^2 = 9604
Total = 19405.
6 years ago
Mayuree Thongpan
6 years ago
Amaline Yang
Thanks
6 years ago
Amaline Yang
Asked 9 years ago
SG
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Primary 5
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Number and Algebra
Help needed! Hate pattern question
Replies
10
Amaline Yang
Thanks
6 years ago
Amaline Yang
How to solve question 3?
6 years ago
Chatawut Che
N(N+1)=1892 = 43×44 43 is the answer
6 years ago
Amaline Yang
6 years ago
Amaline Yang
I am stuck here. How to find n?
6 years ago
Chatawut Che
N(N+1) is the product of two consecutive numbers. Let s try 40x40 =1600 45×45=2025 so N shall be in range between 40 and 44. In this range there are only 41x42 and 43x44 end with 2.
6 years ago
Thit Mon Mon Win
Base* high+1 (base-1=high)
2*1+1=3
3*2+1=7
6 years ago
Adrian Ng
6 years ago
Thit Mon Mon Win
Pattern 1, base=1+pattern no.
6 years ago
Vera Koh
Amaline, try square rooting 1892.. that will give u a good estimation of "n".. after u get the square root, work with the numbers close to it. much faster than guessing, I feel. :)