\(100:\left\{250:\left[450-\left(4\cdot5^3-2^2\cdot25\right)\right]\right\}\)
\(=100:\left\{250:\left[450-\left(500-100\right)\right]\right\}\)
\(=100:\left[250:\left(450-400\right)\right]\)
\(=100:\left(250:50\right)\)
\(=\dfrac{100}{5}\)
\(=20\)
.=100:{250:[450-(4.125-4.25)]}
=100:{250:[450-4.(125-25)]}
=100:{250:[450-4.100]}
=100:{250:50}
=100:5
=20
\(100:\left\{250:\left[450-\left(4.5^3-2^2.25\right)\right]\right\}\)
\(=100:\left\{250:\left[450-\left(500-100\right)\right]\right\}\)
\(=100:\left\{250:\left[450-400\right]\right\}\)
\(=100:\left\{250:50\right\}\)
\(=100:5\)
\(=20\)