How many bit strings of length 12 contain exactly three "1s"

The figure above shows the lengths of thesides of a rectangle in cm. find the valuesof x and y and then the area of the rectangle. sides: top= 3x - yleft= 3y + 4bottom= 2x + yright= 2x - 3 use both methods, elimination and substitution, if possible.

Hiroaki wants to find 3 3/4 - 7/8 explain why he must rename 3 3/4 to do the subtraction.

The length of a rectangular piece of land is 92 yards more than three times its width. the perimeter is 760 yards. find its dimensions.