## Thinking Mathematically (6th Edition)

$1526_{seven}$
Rightmost column: $2$+4=$6$=$6\times 1$=$6_{seven}$ record the $6$, no carry. $\left[\begin{array}{llll} & & & \\ & 6 & 3 & 2_{seven}\\ + & 5 & 6 & 4_{seven}\\ - & - & - & -\\ & & & 6_{seven} \end{array}\right.$ Next column: $3+6=9=1\times7+2\times1=12_{seven}$ record the 2, carry the 1. $\left[\begin{array}{llll} & 1 & & \\ & 6 & 3 & 2_{seven}\\ + & 5 & 6 & 4_{seven}\\ - & - & - & -\\ & & 2 & 6_{seven} \end{array}\right.$ Next column: $1+6+5=12=1\times7+5\times1=12_{seven}$ record the $15$, $\left[\begin{array}{llll} & 1 & & \\ & 6 & 3 & 2_{seven}\\ + & 5 & 6 & 4_{seven}\\ - & - & - & -\\ 1 & 5 & 2 & 6_{seven} \end{array}\right.$