\(a)\) \(x + {\rm{ }}25{\rm{ }} + {\rm{ }}\left( {{\rm{ }} - 17{\rm{ }}} \right){\rm{ }} + {\rm{ }}63 \)\(= x + \left[ {\left( {25 + 63} \right) + \left( { - 17} \right)} \right]\) \(=x + \left[ {88 + \left( { - 17} \right)} \right] = x + 71\)
\(b)\, ( -75) – (p + 20 ) + 95\)\( = (-75) – p – 20 + 95\) \(= -p +( 95 – 75 – 20 )\)\( = - p + 0 = -p \)
