joel subtract the 5% sales tax.
the correct expression is
1.05(190)(0.8) = $159.60
flip each 45-45-90 triangle inwards (we can do this because it is a square and squares have all four sides equal). you should get a plain old shaded square, which means that the shaded square is half of the area of the square with side length 16 cm. so, we have (16 cm)^2 or 256 cm^2, which, when halved, is 128 cm^2 or b.
note: is it a coincidence that it is half? does this always happen? ; )
hello : 1.8
the number is 1.5% of 120 is : ( 1.5×120)/100 = 1.8