The pages in a book are numbered from 1 to 256. how many times is the digit 4 printed

Problem fathi wants to print out a pdf document that is 48 pages long. to save paper, he decides to print on both sides of each sheet and to print two pages on each side of the sheet. how many sheets of paper will he need?

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.

If w = 6 units, x = 3 units, and y = 5 units, what is the surface area of the figure? 168 units2 240 units2 144 units2 96 units2