-pari-
Active Member
have some maths Q from my revision. they're not past paper Q...
1) the cost of running a car at an average speed of v km/h is given by c = 15 + (v^2)/80 cents per hour
find the average speed to the nearest km/h at which the cost of a 500 km trip is a minimum.
answer from memory: 110
2) amy and kevin worked out that they would save $50 000 in 5 years by depositing all of their combined monthly salary of $S at the beginning of each month into a savings account and withdrawing $1600 at the end of each month for living expenses. the savings account paid interest at the rate of 3% p/a compounded monthly.
-a)show that at the end of the 2nd month the balance in their savings account, immediately after making their withdrawal of $1600, would be given by
S[(1.0025^2 - 1.0025) S - 1600 (1.0025 + 1) ]
-b) hence write down an expression for the balance in their account at the end of the sixtieth month
c) calculate their combined monthly savings. answer: $2367.52
3) a man wishes to have %20 000 in 15years time. he proposes to make a finance company 15 equal payments commencing now (the last payment being made 1 year before $20 000 is to be paid to him). Assuming interest is paid by the company at 12% p.a. find what should be the amount of each payment.
4) Two men, Dave and Carl work on an annual salary of $10 000. Dave recieves an increment of $1000 p.a. whilst Carl recieves an increment of $500 every 6months. Who has recieved the greater amount after 10 years and by how much?
answer: Carl, by $2500
5) Ben starts with a salary of $390/wk and recieves a half yearly increase of $30 /wk.
1 year = 52 weeks; find the total amound received during the first n years.
answer: 780n(25+2n)
1) the cost of running a car at an average speed of v km/h is given by c = 15 + (v^2)/80 cents per hour
find the average speed to the nearest km/h at which the cost of a 500 km trip is a minimum.
answer from memory: 110
2) amy and kevin worked out that they would save $50 000 in 5 years by depositing all of their combined monthly salary of $S at the beginning of each month into a savings account and withdrawing $1600 at the end of each month for living expenses. the savings account paid interest at the rate of 3% p/a compounded monthly.
-a)show that at the end of the 2nd month the balance in their savings account, immediately after making their withdrawal of $1600, would be given by
S[(1.0025^2 - 1.0025) S - 1600 (1.0025 + 1) ]
-b) hence write down an expression for the balance in their account at the end of the sixtieth month
c) calculate their combined monthly savings. answer: $2367.52
3) a man wishes to have %20 000 in 15years time. he proposes to make a finance company 15 equal payments commencing now (the last payment being made 1 year before $20 000 is to be paid to him). Assuming interest is paid by the company at 12% p.a. find what should be the amount of each payment.
4) Two men, Dave and Carl work on an annual salary of $10 000. Dave recieves an increment of $1000 p.a. whilst Carl recieves an increment of $500 every 6months. Who has recieved the greater amount after 10 years and by how much?
answer: Carl, by $2500
5) Ben starts with a salary of $390/wk and recieves a half yearly increase of $30 /wk.
1 year = 52 weeks; find the total amound received during the first n years.
answer: 780n(25+2n)