The fifty people at a library are only allowed to sit in groups of 3,4, or 5 people. If all 50 people are seated, the greatest possible number of groups is

16

Step-by-step explanation:

50÷3=16R2

Second largest multiple of 3 that is smaller than 50=45

45÷3=15 groups of 3 people each

50-45=5

         =1 group of 5 people

Greatest possible number of groups=15+1

                                                            =16

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47