Using google translate:
When photocopying a credential, it is first enlarged to triple and subsequently the resulting copy is halved. What is the final effect on the original credential? If the credentials is a rectangle of 10 by 6 cm. What area will you have in the first photocopy? And in the second?
Original: 10 by 6 cm ; Area = length * width = 10 x 6 = 60 cm²
first copy: enlarged to triple
10 x 3 = 30
6 x 3 = 18
30 x 18 = 540 cm²
second copy: halved
30 x 1/2 = 15
18 x 1/2 = 9
15 x 9 = 135 cm²
I'm pretty sure that the answer is 12C4 = (12p4)/4! = (12*11*10*9)/4*3*2*1 = 495
Hope this helps
37.5*0.010=.375 (or press % button on calculator)
80*.375=30