human
Recognise and use efficient strategies for mental addition This is how Ron calculates the answer to \( 46+28 \) mentally ![Cartoon picture of a boy's head with 2 thought bubbles:
First thought bubble says: "46+20 is equal to 66"
Second thought bubble says: "Then I am going to add on the 8.  66+8=74"]() Ron uses the same method to calculate \( 38+45 \). 
Which of the following shows how he would do this? \( \begin{array}{c}38+40=78 \\ 78+5=83\end{array} \)
gpt
Does not copy a given method accurately