Đáp án+Giải thích các bước giải:
$\text{a) $\dfrac{11}{12}$ - $\dfrac{2}{3}$ + $\dfrac{1}{4}$}$
`= 11/12 - 2/3 + 1/4`
`= 1/4 + 1/4`
`= 1/2`
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`b) 190 × 64 + 190 × 3`
`= 190 × (64 + 3)`
`= 190 × 67`
`= 12730`
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`c) 2001 × 2020 - 2000`
`= (2000 + 1) × 2020 - 2000`
`= 2020 × 2000 + 2020 - 2000`
`= 2000 × 2020 + 20`
`= 4040000 + 20`
`= 4040020`