Nata is solving 42 × 15.

Question

Lulu stops her after the third step to ask her why she wrote what she did.
Lulu asks why she wrote a 20.

Complete the sentences to explain Nata’s work.
In this step, Nata multiplied ___
.

.

Answer 1

In this step, Nata multiplied 2 (the units digit of 15) by 42 to find the value of 2 times 42, which equals 84.

When Nata wrote a 20, she was actually calculating the tens part of the multiplication. She took the 1 (the tens digit of 15) and multiplied it by 42, which is essentially multiplying 42 by 10, resulting in 420. However, if she only wrote 20, there might be a misunderstanding or miscalculation at that point.

To clarify, in this step, Nata probably intended to account for the tens place (1 in 15) correctly to eventually add it to the result she got for the units place (84).