Question

Dada a P.A. (5,x,10), qual o valor de x?

Answer 1

$\boxed{\begin{array}{l}\sf a_3=a_1+2r\\\sf 10=5+2r\\\sf 2r=10-5\\\sf 2r=5\\\sf r=\dfrac{5}{2}\\\sf x=5+\dfrac{5}{2}=\dfrac{15}{2}\end{array}}$