There are 10 history books in a bookcase. When the number of books increases by x percent, the
new number of history books is 24. What is the
value of x?
A) 58
B) 70
C) 120
D) 140​

Will mark brainliest question in the pic.

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?

What is always true when two whole numbers are subtracted?