



 
Sandra, The first problem is called a mixture problem. If you go to the Quandaries and Queries page on Math Central and use the Quick Search to search for the word mixture you will find a number of problems of this type and their solutions. For problem 2 he height of each tree is the initial height plus the number of years times its growth rate. So if Y = the number of years, then the hemlock's height is 14 + 4Y. What is the spruce tree's height? You know from the question that at some point, they are the same height, so these two expressions are equal. Solve for Y. Cheers,  


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