What’s Goin’ On In Room 133

Posts Tagged ‘simple interest’

Well, it’s righteous if you can calculate it – Interest, that is!  Because that’s what prt is right?  Principle x rate x time = Interest, right?  And if I give you any three of those four elements (interest, principle, interest rate, or time), you should be able to calculate the fourth right?  Well, let’s see if you remember!

Sierra deposited $1,050 in a savings account, and it earned $241.50 in simple interest after four years.  Find the interest rate on Sierra’s savings account.  (Hint – this is the one I showed you Friday.  Your turn!)

Some people…got to have it…some people…really need it.  Some people…uh, sorry – got a little carried away there.

But seriously, this simple interest stuff really is good stuff.  Remember the formula: I=prt.  As long as you’re multiplying in decimal form eveything is good.  You know, the deposit or loan say, $5,000.00 is already in decimal form, basically dollars and cents.  The interest rate, say, 7.5%, needs to be in decimal form.  That would be 0.075, right?  And the time needs to be in years.  If it’s for 2 years, you would just multiply by 2.  But if it is 3 months then you have to use the decimal equivalent in years.  Three months is one quarter of a year, right?  So instead of multiplying by 3 months, you would have to multiply by 0.25 years, right?  Works for me!  So in this little scenario, the interest on the deposit/loan works out to be $5,000 x 0.075 x 0.25 = $93.75.  Looking gooood!

Now git your groove on with page 359, numbers 3 – 7.  Manana!