Rational numbers: ordering and the four operations
Put negative fractions and decimals on one number line, compare them, then add and multiply them as moves and as scalings.
π Start here: read the steps of the βLessonβ in order (1, 2, 3 β¦) and answer each question. Then continue with βPracticeβ.
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Guide
A rational number is any number you can write as a fraction of two integers: 23, β34, β0.6 (which is β35) and β1 are all rational.
β34 is the opposite of 34: three quarters of the way from 0 towards β1. The minus sign belongs to the whole fraction, so β34 is the same as β34 and 3β4.
On the number line, numbers get bigger from left to right, for fractions too. β12 is further from zero than β13, so it is further left and smaller: β12 < β13.
Adding a fraction is a move along the line: right for a positive one, left for a negative one. Multiplying by a fraction scales the distance from zero: Γ 34 keeps three quarters of it, on the same side.