Thực hiện phép tính:a, \(24.64+24.36-120.\)b. \(2448:\left[119-\left(23-6\right)\right]\).
a,\(24.64+24.36-120\)\(=24.\left(64+36\right)-120\)\(=24.100-120\)\(=2400-120\)\(=2280.\)b, \(2448:\left[119-\left(23-6\right)\right]\)\(=2448:\left[119-17\right]\)\(=2448:102\)\(=24.\)
Tìm x biết:\(\left(2600+6400\right)-3.x=1200\).
\(\left(2600+6400\right)-3.x=1200\) \(9000-3.x=1200\) \(3.x=9000-1200\) \(3.x=7800\) \(x=7800:3\) \(x=2600.\)
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