Simple calculation of 213 × 456 △ 687 △ 456 × 687 △ 213 Be clear

213×456÷687÷456×687÷213
= (213×456÷687)÷456×687÷213
= (213÷687)×687÷213
= 213÷213
=1

How to calculate 15.83 - (4.19-2.83)

=15.83-2.83+4.19
=13+4.19
=17.19

Simple operation of 9 and 3 / 4-15 / 19-2 / 19 * 2

=9 3 / 4-15 / 19-2 * 2 / 19 = 9 3 / 4-15 / 19-4 / 19 = 9 3 / 4 - (15 / 19 + 4 / 19) = 9 3 / 4-1 = 8 3 / 4

-A simple operation of multiplying 8 / 19 by 3

-19 and 8 / 9 × 3
＝[-20+（1/9）]×3
＝-20×3+（1/9）×3
＝-60+（1/3）
= - 59 and 2 / 3

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