Let R be a relation from the set $\left\{1,2,3,.....,60\right\}$ to itself such that R = $\left\{\left(a,b\right):b=pq\right\}$ where p, q $\ge$ 3 are prime numbers. Then, the number of elements in R is:

<p>R = { (a, b): b = pq, where p, q&nbsp;<math><mrow><mo>≥</mo><mn>3</mn></mrow></math>&nbsp;are prime}</p><p><math><mrow><mo>⇒</mo><mn>6</mn><mn>0</mn><mo>×</mo><mn>1</mn><mn>1</mn><mo>=</mo><mn>6</mn><mn>6</mn><mn>0</mn></mrow></math></p><p><img ></p><p>p, q&nbsp;<math><mrow><mo>∈</mo></mrow></math>&nbsp; {3, 5, 7, 11, 13, 17, 19, 23, 29, 3, 37, 41, 43, 47, 53, 59} total 16</p><p>p, q&nbsp;<math><mrow><mo>∈</mo></mrow></math>&nbsp; {3, 5, 7, 11, 13, 17, 19}</p><p><img ></p><p> {3, 5, 7, 11, 13, 17, 19}</p><p>7 + 3 + 1 = 11</p>

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