Final answer:
To solve for the number of Evergreen trees, we set up and solved an algebraic equation based on the given ratio and difference in the number of trees. The number of Evergreen trees is found to be 300, which is not listed in the provided options; thus, there might be an error in the provided options or in the interpretation of the question.
Step-by-step explanation:
The student is asking for help with a ratio and algebra problem related to the number of Evergreen trees to Chestnut trees. Given a ratio of 5:7 and that there are 120 more Chestnut trees than Evergreen trees, we can set up an equation to solve for the number of Evergreen trees. Let the number of Evergreen trees be represented by E, and the number of Chestnut trees be represented by C. According to the ratio, C = (7/5)E. Also, it is given that C is 120 more than E, so C = E + 120.
By substituting (7/5)E for C in the second equation, we get (7/5)E = E + 120. Solving the equation for E, we would multiply both sides by 5 to eliminate the fraction, which gives us 7E = 5E + 600. Subtracting 5E from both sides, we get 2E = 600, and finally, dividing both sides by 2 gives us E = 300. Therefore, there are 300 Evergreen trees in Spring Valley.