There were 280 T-shirts at a boutique. ³₇ of them were without collars. T-shirts without collars were priced at $9 each. T-shirts with collars were priced at $7 each. The boutique owner sold ³₅ of the T-shirts without collars and ⁴₅ of the T-shirts with collars. How much did he collect from all the T-shirts he sold?
Number of T-shirts = 7 u

7 u = 280

1 u = 280 ÷ 7 = 40

Number of T-shirts without collars
= 3 u
= 3 x 40
= 120

Number of T-shirts without collars sold 
= ³₅ x 120
= 72

Number of T-shirts with collars
= 4 u
= 4 x 40
= 160

Number of T-shirts with collars sold
= ⁴₅ x 160
= 128

Amount that the boutique owner collected from the sale of the T-shirts without collars
= 72 x 9
= $648

Amount that the boutique owner collected from the sale of the T-shirts with collars
= 128 x 7
= $896

Total amount that the boutique owner collected from all the T-shirts he sold
= 648 + 896
= $1544

Answer(s): $1544