Three of the angles of a quadrilateral are 1200, 480 and 920. What is the size of the 4th angle?

If the relative frequency of getting a ‘six’ on a dice is 0.2, how many sixes would you expect to get in 200 throws of the dice?

Work out the value of: 3x + 2y
When x = 5 and y = -4

plz number the answers so i know which one is which
need them in 15 mins plz
crown for right answers

Which of the following is a proper fraction? a. 9⁄8 b. 5⁄6 c. 7⁄3 d. 4⁄2

Aprisoner is trapped in a cell containing three doors. the first door leads to a tunnel that returns him to his cell after two days of travel. the second leads to a tunnel that returns him to his cell after three days of travel. the third door leads immediately to freedom. (a) assuming that the prisoner will always select doors 1, 2 and 3 with probabili- ties 0.5,0.3,0.2 (respectively), what is the expected number of days until he reaches freedom? (b) assuming that the prisoner is always equally likely to choose among those doors that he has not used, what is the expected number of days until he reaches freedom? (in this version, if the prisoner initially tries door 1, for example, then when he returns to the cell, he will now select only from doors 2 and 3.) (c) for parts (a) and (b), find the variance of the number of days until the prisoner reaches freedom. hint for part (b): define ni to be the number of additional days the prisoner spends after initially choosing door i and returning to his cell.

Randy and trey take turns cleaning offices on the weekends. it takes randy at most 4 hours to clean the offices. it takes trey at most 6 hours to clean the offices. what is the greatest amount of time it would take them to clean the offices together? 2.4 hours 2.5 hours