## Elementary Statistics (12th Edition)

$z_1=\frac{value-mean}{standard \ deviation}=\frac{133-100}{15}=2.2.$ $z_2=\frac{value-mean}{standard \ deviation}=\frac{79-100}{15}=-1.4.$ Using the table, the value belonging to 2.2: 0.9861, the table, the value belonging to -1.4: 0.0808. 0.9861-0.0808=0.9053.