420 If you get difficult to multiply decimal numbers, eliminate the decimal point:
10.50 x 40 = 1,050/100 x 40 =1,050/(100/20) x 40/20 = 1,050/5 x 2 = 210 x 2 = 420
40% = 0.4 Therefore, 40% off of $1050 = $1050 - (0.4 x $1050) = $630
Because the wavelength is not 1050 metres but 1050 nanometres.
1050
1 multiplied by 40 equals 40.
the value of 30 multiplied by 40 is 1,20030 multiplied by 40 is 1,200
40 multiplied by 9 is 360
40 multiplied by 11 is 440
55 multiplied by 40 equals 2,200.
8 multiplied by 5 is 40.
600,00
20x2=40
40 multiplied by 80 is 3,200