WORD PROBLEMS ON ADDING AND SUBTRACTING POSITIVE AND NEGATIVE NUMBERS

Problem 1 :

When Steve woke up. His temperature was 102^º F. Two hours later it was 3^º lower. What was his temperature then ?

Solution :

Temperature = 102^º F

Two hours later it was 3^º lower = 102^º - 3^º

= 99^º

So, the temperature is 99^º.

Problem 2 :

An elevator is on the twentieth floor. It goes down 11 floors and then up 5 floors. What floor is the elevator on now ?

Solution :

An elevator is on the twentieth floor.

It goes down 11 floors = -11

= 20 + (-11)

= 9^th floor

It goes up 5 floor.

= 9 + 5

= 14^th floor

So, 14^th floor is the elevator on now.

Problem 3 :

A deep – sea exploring ship is pulling up a diver at the rate of 25 feet per minute. The diver is 200 feet below sea level. How deep was the diver 10 minutes ago ?

Solution :

Rate of pulling up a diver is 25 feet per minute.

Distance covered in 10 minutes :

= 25 × 10

= 250 feet

His position now = 200 ft

= 200 + 250

= 450

Problem 4 :

If it is 5^º outside and the temperature will drop 17^º in the next six hours,  how cold will it get ?

Solution :

The temperature will drop 17^º.

If it is 5^ºoutside.

= 5^º - 17^º

= -12^º

Problem 5 :

Josie has $47 left on her checking account. If she writes a check for $55, what will Josie’s balance be ?

Solution :

Josie has $47 left on her checking account.

She writes a check for $55.

= $47 - $55

So, Josie’s balance is -$8.

Problem 6 :

Joe is playing a game with a regular die. If the number that turns up is even, he will gain 5 times the number that comes up. If it is odd, he will lose 10 times the number that comes up. He tosses a 3. Express the results as an integer.

Solution :

Joe is playing a game with a regular die.

He will lose 10 times the number that comes up.

He tosses a 3. If it is odd.

= -10 × 3

= -30

Problem 7 :

It will be - 12^º tonight. The weatherman predicts it will be 25^º warmer by noon tomorrow. What will the temperature be by noon tomorrow ?

Solution :

It will be - 12^º tonight.

it will be 25^º warmer by noon tomorrow.

= -12 + 25

= 13

So, the temperature be by noon tomorrow is 13^º.

Problem 8 :

The average temperature at the South Pole is -45^º F. The average temperature on the Equator is 92^º F. How much warmer is the average temperature on the Equator than at the South Pole ?

Solution :

The average temperature at the South Pole is -45^º F.

The average temperature on the Equator is 92^º F.

Average temperature on the Equator than at the South Pole

= The average temperature on the Equator - The average temperature at the South Pole

= 92^º F – (-45^º) F

= 92^º F + 45^º F

= 137^º F

So, the average temperature on the Equator than at the South Pole is 137^º F.

Problem 9 :

Felix reported that the coldest day on record for his town was five times colder than yesterday’s temperature, -4^º C. What was the temperature of the coldest day on record in Felix’ s town ?

Solution :

Five times colder than yesterday’s temperature, -4^º C.

= 5(-4)

= -20^º C

Problem 10 :

The elevation of Mt. Everest is 29,028 feet. The elevation of the Dead Sea is -485 feet. What is the difference in the elevation between Mt. Everest and the Dead Sea ?

Solution :

The elevation of Mt. Everest is 29,028 feet.

The elevation of the Dead Sea is -485 feet.

Difference in the elevation = 29,028 – (-485)

= 29513

So, the difference in the elevation between Mt. Everest and the Dead Sea is 29513.

Problem 11 :

A scuba diver swam 96 feet beneath the surface of the lake. He then climbs up 49 feet. What is his depth now ?

Solution :

A scuba diver is at 96 feet beneath the surface.

He climbs up the feet = 49

= 96 - 49

= 47

So, the depth is 47 feet.

Problem 12 :

The temperature was -3^º C last night. It is now -4^º C. What was the change in temperature ? 

Solution :

The temperature was -3^º C last night.

It is now -4^º C.

The change in temperature = -4 – (-3)

= -4 + 3

= -1

So, the change in temperature is -1^º C.

Problem 13 :

While watching a football game, Lin Chow decided to list yardage gained as positive integers and yardage lost as negative integers. After these plays, Lin recorded 14, -7, and 9. What was the net gain or loss ?

Solution :

After these plays, Lin recorded 14, -7, and 9.

= 14 + (-7) + 9

= 16

So, the net gain or loss is 16.

Problem 14 :

Pythagoras was born about 582 BC. Isaac Newton was born in 1643 AD. How many years apart were they born ?

Solution :

Pythagoras was born = 582 BC

Isaac Newton was born =1643 AD

= 582 + 1643

= 2225

So, they were born in 2225.

Problem 15 :

Sonny has $75 to spend. The purchase he wants to make requires $93. If he borrows the extra money that he needs, how much does he need to borrow ?

Solution :

Sonny has spend the money = $75

The worth of his purchase = $93

= $93 - $75

= $18

He needs to borrow $18.

Problem 16 :

Two golfers completed one round of golf. The first golfer had a score of +6 and the second golfer had a score of -3. How many more shots did the first golfer take ?

Solution :

The first golfer had a score = +6

The second golfer had a score = -3

= 6 – (-3)

= 9

The first golfer take is 9 shots.

Problem 17 :

What is the balance as a result of having a credit of $84 and a debit of $29 ?

Solution :

Credit balance = $84

Debit balance = $29

= $84 - $29

= $55

So, the balance is $55.

Problem 18 :

The freezing point of water is 32^º F. Tim added potassium and found out that the freezing point went down by 8^º F. What was the freezing point of the water with the added potassium ?

Solution :

Freezing point of water is 32^º F

The freezing point went down by 8^º F

= 32^º F - 8^º F

= 24^º F

So, the freezing point of the water with the added potassium is 24^º F.

Problem 19 :

The city’s budget is $8,000,000. The city actually spends $12,000,000 . What is the city’s deficit ?

Solution :

City’s budget  = $8,000,000

City actually spends the money = $12,000,000

City’s deficit = 4,000,000

Problem 20 :

The local movie theater reported losses of $475 each day for three days. What was the loss for three days ?

Solution :

Losses the money for each day for 3 days = $475

After 3 days losses the money = $475 × $3

= $1425

So, loss for three days is $1425.