Câu 22:
a) \(125+70+375+230\)
\(=\left(125+375\right)+\left(70+230\right)\)
\(=500+300\)
\(=800\)
b) \(49.55+45.49\)
\(=2695+2205\)
\(=4900\)
c) \(120:\left\{54-\left[50:2-\left(3^2-2.4\right)\right]\right\}\)
\(=120:\left\{54-\left[50:2-\left(9-2.4\right)\right]\right\}\)
\(=120:\left\{54-\left[50:2-1\right]\right\}\)
\(=120:\left\{54-24\right\}\)
\(=120:30\)
\(=4\)
d) \(25.5.4.27.2\)
\(=\left(25.5\right).\left(2.4\right).27\)
\(=125.8.27\)
\(=1000.27\)
\(=27000\)