$2\;021+1\;571 = $  

$792-54 = $  

$761-58 = $  

$400+181 = $  

$435+84 = $  

$3\;812-105 = $  

$951-311 = $  

$766+151 = $  

$91-77 = $  

$439+9\;728+58 = $