登录
$5a + 2.6a =$
$6.5a + 3.5a =$
$3mn - 2mn =$
$8.2x - 1.9x =$
$10c - 4.3c =$
$xy - 0.7xy =$
$7.2c - 2.6c =$
$x + 0.7x =$
$x × 16 =$
$b × c =$
$8.2 - 2 × y =$
$a × 1 =$
$m × m =$
$2.5 × k × 4 =$
$7m + 5m =$
$10n - n =$
$b - 0.15b =$
$a × a × 8 =$
$12x + 7x =$
$15 × a =$
$6.5a + 3.5a =$
$3mn - 2mn =$
$8.2x - 1.9x =$
$10c - 4.3c =$
$xy - 0.7xy =$
$7.2c - 2.6c =$
$x + 0.7x =$
$x × 16 =$
$b × c =$
$8.2 - 2 × y =$
$a × 1 =$
$m × m =$
$2.5 × k × 4 =$
$7m + 5m =$
$10n - n =$
$b - 0.15b =$
$a × a × 8 =$
$12x + 7x =$
$15 × a =$
答案
1. 7.6a 10a mn 6.3x 5.7c 0.3xy 4.6c 1.7x 16x bc 8.2−2y a m² 10k 12m 9n 0.85b 8a² 19x 15a
0.76×45= 
63÷42=
☆7.56÷18=
40.8÷24=
7.07×28=
3.85÷350=
7.62×15=
9.2÷23=
☆1.2×48=
63÷42=
☆7.56÷18=
40.8÷24=
7.07×28=
3.85÷350=
7.62×15=
9.2÷23=
☆1.2×48=
答案
2. 34.2 1.5 0.42 1.7 197.96 0.011 114.3 0.4 57.6
（竖式及验算略）
（竖式及验算略）
如图，钉子板上围成的多边形的面积是（
5.5
）cm²。答案
3. 5.5
