# for each situation, find a linear model and use it to make a prediction.?

A.) the cost of producing 4 units is \$204.80. The cost of producing 8 units is \$209.60. How much does it cost to produce 12 units?

B.) there were 174 words typed in 3 minutes. There were 348 words typed in 6 minutes. How many words will be typed in 8 minutes?

D.) After 5 months the number of subscribers to a newspaper was 5830. After 7 months the number of subscribers to teh newspaper was 6022. How many subscribers to teh newspaper will there be afte 10 months?

Relevance

A)

Assuming a linear model, The cost of producing additional 4 units from 4 to 8 is \$209.60 - \$204.80 = 4.80

Cost to produce 12 units (4 units from 8) = \$209.60 + 4.80 = \$214.40

B).

No. of words per minute = 174/3 = 58 wpm

= 348/6 = 58wpm

No. of word in 8 minutes = 8 min(58wpm) = 464 words

D)

Additional subscription in 2 months = 6022 - 5830 = 192 per 2 months

= 192/2 = 96 additional subscription per month

After 10 months = 5830 + (10 - 5)96 = 6310

• cidyah
Lv 7

1)

x1= 4 y1= 204.80 x2= 8 y2= 209.60

solpe = (y2-y1)/(x2-x1)

= (209.6-(204.8))/(8-(4))

= (209.6-204.8)/(8-4)

slope= 4.8

b = (y1-m*x1)

b =204.8-[(4.8)/(4)](4) = 200

Equation: y= mx +b , m = slope

Equation of the line is : y = 4.8 x +200

plug x=12 into the above

y = 4.8(12)+200 = \$257.60

2)

x1= 174 y1= 8 x2= 348 y2= 6

solpe = (y2-y1)/(x2-x1)

= (6-(8))/(348-(174))

= (6-8)/(348-174)

slope= -2/174

b = (y1-m*x1)

b =8-[(-2)/(174)](174) = 10

Equation: y= mx +b , m = slope

Equation of the line is : y = -2/174 x +10

plug x=8 into the equation

y = -2/174 (8) +10 = 10-0.09 = 9.91

c) similar to (a) and (b)