直接写出得数=3.9×=9÷====3+1%==

25%×4=	3.7+15%=	72÷80%=	$\text{[math]}$ - $\text{[math]}$ ×0=
$\text{[math]}$ ÷ $\text{[math]}$ =	37.5%- $\text{[math]}$ =	32×3.14=	$\text{[math]}$ × $\text{[math]}$ =

口算与估算容易

$\text{[math]}$ ×5=	28×20%=	$\text{[math]}$ ÷ $\text{[math]}$ =	4- $\text{[math]}$ =
$\text{[math]}$ + $\text{[math]}$ =	$\text{[math]}$ × $\text{[math]}$ =	2.4× $\text{[math]}$ =	30%÷10%=

口算与估算容易

$\text{[math]}$	$\text{[math]}$	$\text{[math]}$
520×20% =	$\text{[math]}$	3÷0.1% =

口算与估算容易

$\text{[math]}$ ×15= $\text{[math]}$ ×2= $\text{[math]}$ × $\text{[math]}$ = $\text{[math]}$ × $\text{[math]}$ =

$\text{[math]}$ ÷ $\text{[math]}$ = $\text{[math]}$ ÷3= $\text{[math]}$ ÷5= $\text{[math]}$ ÷ $\text{[math]}$ =

口算与估算普通

口算与估算普通