Emily walked to a post box and back and her journey is shown on the distance- time graph below.
She walked home at a constant speed of 2 m/s.
Work out the value of t.
130
Distance from home (m)
90 105
Time (seconds)

The head librarian at the library of congress has asked her assistant for an interval estimate of the mean number of books checked out each day. the assistant provides the following interval estimate: from 740 to 920 books per day. what is an efficient, unbiased point estimate of the number of books checked out each day at the library of congress?

How long does it take natsumi to clean up after she is done? table: .area time30. 245. 2.7560. 3.5

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?