document.write( "Question 435669: Jasmine has accepted a new job with an interesting pay scale. She will earn $ 10 for the first month, $ 20 for the second month, $ 40 for the third month, and so on. Each month her salary will be twice that of the previous month. Develop a formula that will give Jasmine's total income through n months. How much will she have received after 2 years, giving your answer in standard form correct to two significant figures? \n" ); document.write( "
Algebra.Com's Answer #301569 by htmentor(1343) You can put this solution on YOUR website! We need to find the accumulated salary through n months. \n" ); document.write( "Let's look at the first few months. \n" ); document.write( "Let S(n) = the total salary through the n-th month \n" ); document.write( "We can write: \n" ); document.write( "S(1) = 10 \n" ); document.write( "S(2) = 10 + 20 = 30 \n" ); document.write( "S(3) = 30 + 40 = 70 \n" ); document.write( "S(4) = 70 + 80 = 150 \n" ); document.write( "Now we try to find an expression for S(n) in terms of S(1): \n" ); document.write( "S(2) = S(1) + 20 = S(1) + 2S(1) = 3S(1) \n" ); document.write( "S(3) = S(2) + 40 = S(2) + 4S(1) = S(1) + 2S(1) + 4S(1) = 7S(1) \n" ); document.write( "For a given n, the multiplier can then be expressed as \n" ); document.write( "So, in general, we can write: \n" ); document.write( " \n" ); document.write( "Let's check our formula for n=4 \n" ); document.write( "S(4) = (2^4 - 1)S(1) = 15S(1) = 150 \n" ); document.write( "After 2 years, the total salary will be: \n" ); document.write( "S(24) = (2^24 - 1)S(1) = $167,772,150 (not sure about the \"standard form\") \n" ); document.write( "The graph below shows the rate at which the cumulative salary grows: \n" ); document.write( " |