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Grade 5

Three problems that reward a second look

A fraction sum that folds up neatly, two fractions a hair apart, and one equation to work backwards -- three chances to look for structure before reaching for arithmetic.

  1. 1

    Quick calculation

    Calculate A=17+191+1247+1475+1775+11147.A = \frac{1}{7} + \frac{1}{91} + \frac{1}{247} + \frac{1}{475} + \frac{1}{775} + \frac{1}{1147}.
  2. 2

    Compare

    Which is bigger: 210222\frac{210}{222} or 1819\frac{18}{19}?
  3. 3

    Find X

    Find XX: 1075−3.75X=1073.5.1075 - \frac{3.75}{X} = 1073.5.