The populations of two cities after t years can be modeled by
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Value of 't' = 4
Difference between the population of the two cities
[tex] \text{{Assuming the population of two cities as}} \: \text{c}_1 \text{ and} \: \text{c}_2[/tex]
[tex] \text{ In Case of }\text{c}_1[/tex]
[tex]\text{c}_1 = -150\text{t} + 50,000 \\ \implies \text{c}_1 = - 150 \times 4 + 50,000 \\ \implies \text{c}_1 = - 600 + 50,000 \\ \implies \text{c}_1 = 49,400[/tex]
[tex] \text{ In Case of }\text{c}_2[/tex]
[tex]\text{c}_2 = 50\text{t} + 75,000 \\ \implies \text{c}_2 = 50\times 4 + 75,000 \\\implies \text{c}_2 = 200+ 75,000 \\ \implies \text{c}_2 = 75,200[/tex]
Now, We need to find the difference in their population
[tex]\text{c}_2 - \text{c}_1 \\ = 75,200 - 49,400 \\ = 25,800[/tex]
[tex]\therefore \text{Difference between their Population=} \red{25,800}[/tex]