Quick Notes

Mango fruit
\(\text{RM }7\) /kg

What is the price of 3 kg for the above mangoes??

METHOD 1

\(\begin{array} {rr} \space\space\text{RM }\space\space\space\space7 \\\times\space\space\space\space\space\space\space\space3 \\\hline\space2\space1 \\\hline \end{array}\)

METHOD 2

\(\begin{array} {rr} \text{RM }7+\text{RM }7+\text{RM }7=\text{RM }21 \end{array}\)