250[1-(1+0.024)^-10]

250[1-(1+0.024)^-10]

$\small{ \begin{array}{lcll} 250\cdot [1-(1+0.024)^{-10}] &=& \qquad & | \qquad 1+0.024 = 1.024\\ &=& 250\cdot \left( 1-1.024^{-10} \right) \qquad & | \qquad 1.024^{-10} = \frac{1}{1.024^{10}}\\ &=& 250\cdot \left( 1-\frac{1}{1.024^{10}} \right) \qquad & | \qquad \frac{1}{1.024^{10}} = 0.7888609052 \\ &=& 250\cdot \left( 1-0.7888609052 \right) \qquad & | \qquad 1-0.7888609052 = 0.2111390948 \\ &=& 250\cdot 0.2111390948\\ &=& 52.7847736947\\ \mathbf{250\cdot [1-(1+0.024)^{-10}] }&\mathbf{=}& \mathbf{52.7847736947} \\ \end{array} }$