The formula this page uses
a/b = a ÷ b. It terminates only when b, in lowest terms, has no prime factors except 2 and 5.
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The visual updates with your calculation.
a/b = a ÷ b. It terminates only when b, in lowest terms, has no prime factors except 2 and 5.
Convert 5/8
Yes. Reduce it first, then factor the bottom number. 7/40 has 40 = 2 × 2 × 2 × 5, so it terminates at 0.175. 7/30 has 30 = 2 × 3 × 5, and that 3 guarantees a repeat. This check takes five seconds and saves a long division that was never going to end.
At most one less than the bottom number, because there are only that many possible remainders before one has to come back. For sevenths the block is six digits long, which is the maximum. For elevenths it is only two, even though ten were allowed.
It marks exactly which digits repeat. In 0.416 with the bar over only the 6, the 4 and 1 happen once and the 6 goes on forever. If the bar covered 416 it would mean 0.416416416…, which is a completely different number.
Convert just the fraction part and add the whole number back on. 3 ÷ 8 = 0.375, so 2 and 3/8 = 2.375. You get the same answer from the improper fraction 19/8, since 19 ÷ 8 = 2.375.
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