Using the 1‑1‑1 smart chart, find the sum of $124$, $57$, and $89$.

Step-by-step solution

1. Write the numbers aligned by place value: $\begin{array}{c}124\\ 057\\ 089\end{array}$
2. Add the units column using the 1‑1‑1 chart: $4+7+9=20$ (carry $2$).
3. Add the tens column plus carry: $2+5+8+2=17$ (carry $1$).
4. Add the hundreds column plus carry: $1+0+0+1=2$.
5. Combine the results to get $270$.
6. final calculation: $200+70+0=270$

Concept tested: 1‑1‑1 chart addition

Published 16 October 2026 · How this solution was prepared and checked