Answer: c) For every extra person attending an event, the time it takes to make arrangements increases by 0.5 hour
y is the time
x is nº of people
When x=1 (one person is attending the dinner):
y= 0,5 x 1 +1.3
y= 1.8 hours
When x=2 (two peple are attending the dinner):
y= 0,5 x 2 +1.3
y= 2,3 hours
When x=3 (three people are attending the dinner):
y= 0,5 x 3 +1.3
y= 2,8 hours
the difference between 1.8 and 2.3 h is exactly 0,5 h.
And the difference between 2.3 and 2.8 h is also 0,5 h.
If you continue to increase x, the y will increase 0,5
