Number 15. My school's swimming team is practicing for a relay competition. Five swimmers swim the same distance one after the other. The pictures below show the times on their coaches stopwatch when each swimmer finished their leg. The first swimmer needed two minutes and eight seconds. Which of the swimmers needed the least time? Pause if you want to try and solve it. Okay, so the way we figure this out is by looking at how long each swimmer took. So the first swimmer took two minutes and eight seconds. And the second swimmer finished after four minutes and seven seconds. But we have to subtract the first two minutes and eight seconds because that was how long the first swimmer took. So what's the difference? Well, we can see that if we added two full minutes to two minutes and eight seconds, then we would get four minutes and eight seconds, right? If we added two full minutes, then we would get four minutes and eight seconds. But four minutes and seven seconds is one less than that. So we need to subtract one second. So what's one second less than two minutes? Well, it is one minute and 59 seconds. So for the next one, we can see that the next swimmer finished after six minutes and ten seconds. And we can see pretty clearly that the amount of time we need to add is two minutes to go from four to six, and three seconds to go from seven seconds to ten seconds. So two minutes and three seconds. All right, so now let's look at the next one. We have that the swimmer finished after eight minutes and five seconds. Once again, if we added two full minutes to six minutes and ten seconds, we'd have eight minutes and ten seconds. But that's five less than that, right? Eight minutes and five seconds is five less than eight minutes and ten seconds. So if we do, sorry, this should be a four. If we do five seconds less than two minutes, that's one minute and 55 seconds. All right. And then lastly, using the same trick here, we get that the last swimmer took one minute and 58 seconds. So we can see that the swimmer that took the least amount of time was the fourth swimmer who took one minute and 55 seconds. So the correct answer for number 15 is option D.

relay race

swimmer times

fastest leg

school team

stopwatch