A shop's two branches record their sales of shirts and trousers. March is matrix M and April is matrix N, where row 1 is branch P, row 2 is branch Q, column 1 is shirts and column 2 is trousers. How many trousers did branch Q sell in the two months together?

Question 35

EasyOriginal question

A shop's two branches record their sales of shirts and trousers. March is $M = \begin{bmatrix}40 & 25 \\ 35 & 30\end{bmatrix}$ and April is $N = \begin{bmatrix}45 & 20 \\ 30 & 40\end{bmatrix}$ , where row 1 is branch P, row 2 is branch Q, column 1 is shirts and column 2 is trousers. How many trousers did branch Q sell in the two months together?

45

Correct answerYour answer

65

Correct answerYour answer

70

Correct answerYour answer

75

Correct answerYour answer

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CorrectNot quiteAnswer C

Correct answer: C

The two months together are $M + N = \begin{bmatrix}85 & 45 \\ 65 & 70\end{bmatrix}$ .
Branch Q is row 2 and trousers are column 2: $30 + 40 = 70$ .

Worth noting

45 is branch P's trousers, row 1 instead of row 2.

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