100 students attended a revision lesson at the weekend. Each student went to Maths or English or Science.
55 of these students attended on Saturday.
Over the weekend a total of 40 students went to Maths.
12 of the 27 students that went to Science went on Sunday.
10 students went to English on Saturday.
How many students went to the Maths revision lesson on Saturday?

In the diagram below, dab and dac are adjacent angles. if mdac = 25°, what is mdab in degrees? what is mbac in degrees?

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?

Which value would be a solution for x in the inequality 47-4x< 7