Answer:
x = -30
Step-by-step explanation:
subtract 7 from both sides ( 7+2/5x -7, -5-7 )
simplify ( 2/5x = 12 )
multiply both sides by 5 ( 2/5x times 5 = 5 (-12) )
simplify ( 2x = -60 )
divide both sides by 2 ( 2x / 2, -60 / 2 )
x = -30
To get the answer we can use proportion
86 --------------45%
x ---------------- 100%
Now cross multiply
x*45%=86*100
45x=8600 /:45 (divide both sides by 45)
x=191.11 - its the answer
It would be 78/4=19.5 which would mean that he would be able to set 19 tables. To be able to set all of the tables he would need 2 more napkins because 19*4=76. 78-76=2 so they would need 2 more to finish the last table.
