Write each measurement with the indicated number of significant digits. 454.12; 3 significant digits

One card is dealt from a 52 card deck. find the probability that the dealt card is a 4 or a black 7

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

The length of a rectangle plus its width is 25 cm. the area is 156 square cm. what are the length and width of the rectangle? separate the answers with a comma.