Question

3/12X7/9十9/12÷7/9能用简便方法算吗？

Answer 1

3/12 x7/9 +9/12 ÷7/9
=3x7/(12x9) +9x9/(12x7)
【第一项、第二项用3约分】
=7/(4x9) + 27/(4x7)
【提取1/4】
=(7/9 + 27/7)/4
【通分】
=(7x7+27x9)/(63x4）
=292/(63x4)
【用4约分】
=73/63
=1又10/63

Answer 2

能用简便方法，解题如下:
3/12x7/9+9/12÷7/9
=3/12×7/9+9/12×9/7
=1/4x7/9+3/4×9/7
=1/4(7/9+3x9/7)
=1/4(7/9+27/7)
=1/4(49/63+243/63)
=1/4×292/63
=292/252

追答

能用简便方法，解题如下:
3/12x7/9+9/12÷7/9
=3/12×7/9+9/12×9/7
=1/4x7/9+3/4×9/7
=1/4(7/9+3x9/7)
=1/4(7/9+27/7)
=1/4(49/63+243/63)
=1/4×292/63
=292/252

Answer 3

3/12×7/9+9/12÷7/9
=1/4×7/9+3/4×9/7
=1/4×（7/9+27/7）
=1/4×（49/63+243/63）
=1/4×292/63
=73/63
=1又63分之10

Answer 4