How do we find percentage change?

Mr. Santiago had a salary increase of 5% in August compared to September.

Which statements is true about Mr. Santiago's salary?

Find the percentage change in the following price increase:

Original: $64

Final: $160

Remember:
$$\frac{change}{original\ }x\ 100\%$$

 

Find the new value when $20 is increased by 10%

The height of Tom is 132cm. He is 10% taller than last year. What is his height last year?

Sal's bank account balance increased by 75% from February to March. If he had $2,500 in February, how much does he have in March?

Find the new value when $50 is decreased by 20%

In a wetland, 400 birds were observed in 2018 and 450 birds were observed in 2019. Find the change of the no. of birds.

In a wetland, 400 birds are observed in 2018 and 450 birds are observed in 2019. Find the percentage change of the no. of birds.

The height of Tom is 132cm. He is 10% taller than last year. What is his height last year?

The fee of lunch was $40 per head. It becomes $30 per head this year. Find the change.

The fee of lunch was $40 per head. It becomes $30 per head this year. Find the percentage decrease.

Mr Tam can finish 3000m in 20 min last year and he can do it in 18 min this year. What is the change?

Mr Tam can finish 3000m in 20 min last year and he can do it in 18 min this year. Find the percentage change.

Sal's bank account balance increased by 75% last month. If he started the month with $2,500, how much does he have now?

In 2000, your favorite candy cost $1.25 a pack. Now it costs $2.00 a pack. What was the relative change in the price over that time?

Car B costs $31,000. This is 23% more than car A costs. What is the price of car A, to the nearest dollar?

A rat used to take 350 seconds to complete a maze. He has improved his time by 16%, how long does it take him now, to the nearest second? (Remember, this is a percent decrease from 350 sec.)

B = 35.  A is 125% more than B.  A = ?

B = 35.  A is 25% more than B.  A = ?

$$x=5.5,\ y=7.25$$  .  By what percentage is y greater than x (rounded to 1 decimal place)?

$$x=5.5,\ y=7.25$$  .  What is the percent difference between x and y if y is your reference value?

You just refinanced your home to lower your mortgage rate. Your old rate was 6%. You are now paying 4% interest. What is the absolute change in your rate?

You just refinanced your home to lower your mortgage rate. Your old rate was 6%. You are now paying 4% interest. What is the relative change in your rate to the nearest percent?

Last year, 75% of respondents to a survey were fans of Talking Heads. This year 84% of respondents were fans of the band. What was the absolute change in fan percentage?

Last year, 75% of respondents to a survey were fans of Talking Heads. This year 84% of respondents were fans of the band. What was the relative change in fan percentage?

225.25 is 22% less than x. What is x, to 2 decimal places?

x is 22% greater than 225.25. What is x, to 2 decimal places?

A group of students were surveyed about their music genre preference. 41% of students prefer rock. Relatively, the percent of student who prefer hip hop is 8% greater than those who prefer rock. What percent of students prefer hip hop, to the nearest tenth?

What is 80% of 15%?

Consider this statement: "Car A is 18% more expensive than car B." Which car's price is the reference value?

In 2019, you earned $35,000 and paid taxes at a rate of 8%. Your earnings in 2020 increased by 25% and your tax rate increased to 10%. How much did you pay in taxes in 2020?

An electronics store increased the prices of all laptops by 8%. During the end of year sales, all stock was discounted by 10%. A laptop originally cost $995.

What was the new price of the laptop after the price increase?

Cafe X increased all prices by 10% but then offered a 5% discount to all customers with a Cafe X loyalty card. Before the prices were changed, a coffee cost $4.50. Following the price increase, how much would a coffee cost for a customer with a loyalty card?

At an intersection on a busy road, the number of accidents in 2010 was 35. In 2011 this increased by 20%.

At the start of 2012, a set of traffic lights was put in at the intersection and the number of accidents decreased by 69%.

How many accidents were there at the intersection in 2012? Answer to the nearest whole number.

Prices are reduced by 27% in a sale at SuperMart. Georgia buys a TV, saving £75.60 on the original price. Calculate the original price

1) A camera costs £180 in a 10% sale. What was the pre-sale price?

2) After fuel prices rose by 15%, a family’s annual heating bill was £1654. What would the bill have been without the price increase?

3) The cost of a holiday, including VAT at 20% is £540. What is the pre-VAT price?

4) The world’s tiger population has decreased by 95% since 1910 and is now believed to be as low as 3200. If these figures are correct, what was the tiger population in 1910?

5) The sale price of a television is £420 after a 15% reduction. What was the price before the sale?

6) After a 6.5% pay rise an engineer’s salary is £36,700. What was the salary before the increase?

8) An engine modification improved the fuel consumption of a car by 27% to 17.2 km per litre. What was the fuel consumption before the modification?

9) After a long-haul flight, the total weight of a Boeing 747 had decreased by 27% to 305,000kg. What weight was the aircraft carrying at take-off?

A company's stock price decreased by 10% in one day. If the original price was $50, what is the new price?

If a student scored 75% in a test and another student scored 80%, by how much percentage did the second student score more than the first?

A store increased the price of a product from $60 to $75. What is the percentage increase?

If a population increased from 500 to 600, what is the percentage increase?

A car's value decreased by 25% in one year. If the original value was $20,000, what is the new value?

If a recipe calls for 2 cups of flour and you want to make 50% more, how many cups of flour do you need?