Åk 6–9
 
English/عربي
4.5 Exercise – Changes in percent
1. Write the new value:
a) 75 increases by 20 %
b) 320 decreases by 20 %
c) 110 increases by 10 %
d) 800 increases by 7 %
e) 140 decreases by 5 %
f) 14 increases by 250 %
 

 
2. Write the percentual change:
a) 100 decreases to 60
b) 100 increases to 160
c) 70 increases to 105
d) 970 decreases to 7
e) 40 decreases to 38
f) 18 increases to 180
 
 
3. A mobile telephone from 1996 weighed 200 g.  A year later a new model weight 85 g.  Write a mathematical expression and calculate the proportion of decrease in weight.
 
 

 
4. In 2002, gasoline cost 8.4 kr /l.  Today it costs 10.8 kr/l.  Write the mathematical expression and calculate the proportion of increase in price.  Round your answer to tenths.
 
 
 
5. A two year old child is on average 86 cm tall.  A three year old is on average 92 cm.  Write a mathematical expression and calculate the proportional increase.  Round your answer to a whole number in percent.
 
 
 
6. A store decreased the price of a camera from 900 kr to 783.  Write a mathematical expression and calculate the rate of change.  Round your answer to three decimals.
 
 
 
7. After a rain storm, the mass of a water holder increased from 10.4 kg to 13.6.  Write a mathematical expression and calculate the rate of change.  Round your answer to three decimals.
 
 
 
8. You deposit 30,000 kr into a savings account with a yearly interest rate of 6 %.  After 3 years, you have 35,730.  Write a mathematical expression and calculate the rate of change.