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TIMO - 2021 - Grade 7 - Preliminary Round - Paper 5 Question 7

TIMO · TIMO - 2021 - Grade 7 - Preliminary Round - Paper 5

Question 7

Find $\frac1{1\times3}+\frac1{3\times5}+\frac1{5\times7}+\cdots+\frac1{107\times109}+\frac1{109\times111}$.
  1. $\frac{50}{111}$
  2. $\frac{220}{111}$
  3. $\frac{110}{111}$
  4. $\frac{55}{111}$