Let S be the No. of Sweat shirts and T be the No. of T-shirts.

Hence S+T =1200 …..(A)

And 14S+8T =11400 …….(B)

Multiply Eq (A) by 14 and subtract Eq (B) therefrom

We will have 6T= 16800-11400

6T=5400

T=900 and therefore S=300

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