Answer:
$848
Explanation:
Calculation for the cost of this familiy's clothing in 1991
First step is to calculate the amount that is increase per year
Increase per year= ($1000-$620)/(1995-1985)
Increase per year= 380/10
Increase per year= $38
Now let y be :38*x + $620 and let x be 6 years (1991-1985)
Second step is to calculate the cost of the clothing in 1991
y = 38*6 + 620
y=228+620
y = $848
Therefore the cost of this familiy's clothing in 1991 will be $848