Page 240 - NUMINO TG_6A
P. 240
15Buying Items on Sale Unit
CMath Vo abulary principal: the original amount of money used to find interest
simple interest: a fixed percent of principal that is paid yearly
2 . Solve the word problems. 2. Have students solve the word problems
Ricky deposits $50 in the bank at an annual simple interest with partners. For these problems, students
rate of 4%. How much money will Ricky get back from the
bank 2 years later? must calculate the simple interest and then
add it back to the principal. Have them follow
p = $50, r = 0.04, t = 2 these steps: refer to .
total amount = p I Plug the numbers into the simple interest
= $50 $4
I=p r t = $54 formula.
= $50 0.04
= $4 2 Find the simple interest.
Add the simple interest plus the principal
Ricky will get $54 from the bank 2 years later. to find the total amount of money in the
a. Ann deposits $200 in the bank at an annual simple interest rate of 7%. bank.
How much money will Ann get back from the bank 3 years later? Have students discuss the pros and cons of
saving money to buy an item versus
p = $200, r = 0.07, t = 3 borrowing money to pay for it.
I=p r t 3 total amount = p I
= $200 0.07 = $200 $42
= $42 = $242
Ann will get $242 from the bank 3 years later.
b. Kate deposits $400 in the bank at an annual simple interest rate of 5.5%.
How much money will Kate get from the bank 6 years later?
p = $400, r = 0.055, t = 6
I=p r t 6 total amount = p I
= $400 0.055 = $400 $132
= $132 = $532
Kate will get $532 from the bank 6 years later.
c. Ryan borrowed $150 from the bank at an annual simple interest rate of 8%.
How much money does Ryan have to pay back 3 years later?
p = $150, r = 0.08, t = 3
I=p r t 3 total amount = p I
= $150 0.08 = $150 $36
= $36 = $186
Ryan has to pay back $186 3 years later.
15. Buying Items on Sale 137
The Total Amount of Money
To find the total amount of money after a given time, students need to remember to add the interest to the
principal.
Example: p $50, r 0.04, t 2
Iprt
I $50 0.04 2
I $4
Total amount p I $50 $4 $54
6A Unit 15 223
CMath Vo abulary principal: the original amount of money used to find interest
simple interest: a fixed percent of principal that is paid yearly
2 . Solve the word problems. 2. Have students solve the word problems
Ricky deposits $50 in the bank at an annual simple interest with partners. For these problems, students
rate of 4%. How much money will Ricky get back from the
bank 2 years later? must calculate the simple interest and then
add it back to the principal. Have them follow
p = $50, r = 0.04, t = 2 these steps: refer to .
total amount = p I Plug the numbers into the simple interest
= $50 $4
I=p r t = $54 formula.
= $50 0.04
= $4 2 Find the simple interest.
Add the simple interest plus the principal
Ricky will get $54 from the bank 2 years later. to find the total amount of money in the
a. Ann deposits $200 in the bank at an annual simple interest rate of 7%. bank.
How much money will Ann get back from the bank 3 years later? Have students discuss the pros and cons of
saving money to buy an item versus
p = $200, r = 0.07, t = 3 borrowing money to pay for it.
I=p r t 3 total amount = p I
= $200 0.07 = $200 $42
= $42 = $242
Ann will get $242 from the bank 3 years later.
b. Kate deposits $400 in the bank at an annual simple interest rate of 5.5%.
How much money will Kate get from the bank 6 years later?
p = $400, r = 0.055, t = 6
I=p r t 6 total amount = p I
= $400 0.055 = $400 $132
= $132 = $532
Kate will get $532 from the bank 6 years later.
c. Ryan borrowed $150 from the bank at an annual simple interest rate of 8%.
How much money does Ryan have to pay back 3 years later?
p = $150, r = 0.08, t = 3
I=p r t 3 total amount = p I
= $150 0.08 = $150 $36
= $36 = $186
Ryan has to pay back $186 3 years later.
15. Buying Items on Sale 137
The Total Amount of Money
To find the total amount of money after a given time, students need to remember to add the interest to the
principal.
Example: p $50, r 0.04, t 2
Iprt
I $50 0.04 2
I $4
Total amount p I $50 $4 $54
6A Unit 15 223
