Simple Interest

Simple Interest

Definitions:

I = Interest

p = principle *the original amount you either borrow or save

r = rate *a percent

t = time (in years) *the amount of time you will have to pay back the loan or the amount of time you will earn interest

Simple Interest Formula:

I = prt

To solve problems involving

simple interest, use the formula:

Multiple Choice

$10,000 at 4.2% for 5 years

• I = $2,100

• I = $21,000

• I = $210,000

Multiple Choice

$2,400 at 3.5% for $$5\frac{1}{4}$$ years.

• I = $453.60

• I = $420.00

• I = $441.00

• $4410.00

Multiple Choice

$840 at 3.5% for 9 months

• I = $26,460

• I = $264.60

• I = $22.05

Multiple Choice

$12,400 at 10% for 18 months

• I = $22,320

• I = $1860

• I = $252,000

Math Lib Time!!

Let's go........

Multiple Choice

Jane received $875 from her graduation party. She put the money in a bank with a 4% simple interest rate.

How much interest will she have earned after 7 years?

• $205

  Sammy

• $225

  Ristyn

• $245

  Bailey

• $2250

  Mrs. Fowler

• $2450

  Mrs. Quintana

Multiple Choice

Ethan borrowed $2,190 for a new dirt bike. He will pay the money back in 3 years with a simple interest rate of 2.5%.

How much interest will he pay?

• $164.25

  baffled

• $172.75

  concerned

• $1,642.50

  forced

• $1,727.50

  honored

• $2,354.25

  delighted

Multiple Choice

Colton took out a loan from the bank to purchase a car.

If he borrowed $17,240 at simple interest rate of 8.25%, how much total will he have paid after 5 years?

• $6,894.25

  telling math jokes

• $7,111.50

  building a fort

• $21,548.90

  zip lining

• $22,890.75

  snorkeling

• $24,351.50

  riding camels

Multiple Choice

Stefan borrowed $8,950 for an engagement ring.

At a 6.85% simple interest rate, how much total will he have paid after 6 years?

• $3,378.45

  Taylor Swift

• $37,784.50

  Rihanna

• $12,504.25

  Will Smith

• $12,595.80

  Adam Levine

• $12,628.45

  Miley Cyrus

Multiple Choice

Veronica took out a 48 month loan of $5,500 to make some home improvements.

At a simple interest rate of 3.25%, how much total will she pay?

• $6,740.25

  Memorial Day

• $6,215.00

  Saturday morning

• $6,393.75

  Valentine’s Day

• $6,575.50

  Mardis Gras

• $6,036.25

  last Friday night

Multiple Choice

City Bank offers a 4.75% simple interest rate, while First National offers 3.9%.

If Tom wants to set up a new account with $500, how much more money will he earn in interest at City Bank over First National after 12 years?

• $45

  Las Vegas

• $48

  Philadelphia

• $51

  Hollywood

• $55

  New York City

• $59

  Seattle

Multiple Choice

Jonah earned $150.36 in interest on an account that earns 1.4% simple interest.

If Jonah opened the account 12 years ago, what was the principal amount?

• $850

  the court house

• $868

  the movie theater

• $880

  the art museum

• $895

  the mall

• $902

  the aquarium

Multiple Choice

Scott took out a 72 month loan for $35,000 to purchase a new boat.

If Scott paid $8,925 in simple interest, what was the interest rate?

• 3.5%

  striped leggings

• 4.25%

  chef hats

• 4.5%

  leather jackets

• 4.75%

  rock wigs

• 5.1%

  footed pajamas

Multiple Choice

Abby earned $600 this past summer babysitting. She decided to put this money in a bank that earns a 5% simple interest rate.

How many years will it take to double her initial deposit?

• 10 years

  posting on Facebook

• 12 years

  playing kazoos

• 15 years

  fist pumping

• 18 years

  eating marshmallows

• 20 years

  brushing their teeth

Multiple Choice

Miles is buying a new computer for $1,150. He is considering two credit options.

Option A offers a 3 year loan with a 10% simple interest rate while Option B offers a 5 year loan with a 6.5% simple interest rate.

Which is the better option and how much will he save?

• A; $28.75

  win a radio contest

• A; $32.50

  raise money for charity

• B; $28.75

  get attention

• B; $32.50

  do something crazy

Bailey was baffled to be riding camels with Miley Cyrus on Saturday morning in Hollywood at the mall wearing chef hats while brushing their teeth because they wanted to win a radio contest!

Homework:

Homework 14:
Simple Interest, #1-10