Total number of coins is: 16 + 28 + 32 +4 = 80 coins
He sold 15% of them. "of" means multiply.
80 x 15% is the same as 80 x .15
80 x .15 = 12
He sold 12 coins
4/10 is equal to 4 out of 10 or 40%
This means you should shade 4 of the 10 blocks
If 205 is a posible answer I think thats's it
Because it's just like multiplucation 41x1=41
42x2=82.......etc.
42x5=205