Thực hiện phép tính (tính hợp lí nếu có thể):

a) \({7^{50}}:{7^{48}} - \left( {{6^2} + {{2024}^0}} \right)\)

\( = {7^2} - \left( {36 + 1} \right)\)

\( = 49 - 37\)

\( = 12\).

b) \[\left( {-67} \right) + 125 + \left( {-33} \right) + 75\]

\( = \left[ {\left( { - 67} \right) + \left( { - 33} \right)} \right] + \left( {125 + 75} \right)\)

\( = \left[ { - 100} \right] + 200\)

\[ = 100\].

c) \[43.\left( {57 - 45} \right) + 57.\left( { - 43 - 45} \right)\]

\( = 43.57 - 43.45 + 57.\left( { - 43} \right) - 57.45\)

\( = \left[ {43.57 + 57.\left( { - 43} \right)} \right] + \left( { - 43.45 - 57.45} \right)\)

\[ = 45.\left( { - 43 - 57} \right)\]

\( = 45.\left( { - 100} \right)\)

\( =  - 4\,\,500\).

d) \(53.89 + {6^2}.53 - {53.5^2}\)

\( = 53.\left( {89 + {6^2} - {5^2}} \right)\)

\( = 53.\left( {89 + 36 - 25} \right)\)

\( = 53.100\)

\( = 5\,\,300\).