Evauate 15 divide by r minus 1 when r = 5

Which of the following is correct interpretation of the expression -4+13

Maurice has 54 fewer comic books than rebecca.they have 130 comic books together .how many comic books are in maurices collection ? how many comic books are in rebeccas collection

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?