\(a,21.\left(-15\right)+67.\left(-15\right)+\left(-15\right)+\left(-15\right).12\)
\(=21.\left(-15\right)+67.\left(-15\right)+\left(-15\right).1+\left(-15\right).12\)
\(=-15.\left(21+67+1+12\right)\)\(=-15.101=-1515\)
\(b,\left(-30\right)+76+30\)\(=\left(-30+30\right)+76=0+76=76\)
\(d,15.\left\{22-\left[400:\left(140+12.5\right)\right]\right\}\)
\(=15.\left\{22-\left[400:\left(140+60\right)\right]\right\}\)
\(=15.\left[22-\left(400:200\right)\right]\)
\(=15.\left(22-2\right)=15.20=600\)
a. (-15) x 101 = -1515
b. (-30+30) +76 = 76
a) 21.(-15)+67.(-15)+(-15)+(-15).12
= (-15).(21+67+1+12)
= (-15).101
= -1515
b) (-30)+76+30
= [(-30)+30]+76
= 0+76 = 76
c) 15.{22-[400:(140+12.5)]}
= 15.{22-[400:(140+60)]}
= 15.{22-[400:200]}
= 15.{22-2}
= 15.20
= 300
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