Mental Calculations
(56+72)× 3÷ 15
21
Ten friends have an average of 5 toys cars each. Sam joins them, and now the average is 6 toy cars each. How many toy cars does Sam have?
16
Find the value of a:
27/4, 9/2, 3, a, 4/3
2
What will happen if the quantity demanded of a good is greater than its quantity supplied?
Shortage of the good
Why would competitors open shops near each other (e.g. 老虎堂 幸福堂)?
People who like that particular good/service will visit that area, hence draws more customers for both companies.
2008×1992
3999936
Mom gives Tom 10 candies. He can get one more candy with 2 candy wrapping paper. Assuming that Tom eats all candies he has, in total how many candies can Tom eat?
19
In a sequence of six integers, every term after the second term is the sum of the previous two terms. If the sum of all six terms is 12, what is the first term?
0
Who is the Father of economics?
Adam Smith
Why wouldn’t airline companies increase the wages of their employees despite frequent strikes?
It’s more costly for them to adjust the wages than delaying airlines.
It will, in turn, cause other employees to request for an increase in wage
What is the smallest whole number n for which 528÷ n is a factor of 180?
44
There are 200 chickens and rabbits in a farm. All rabbits have 80 legs more than chickens in total. How many rabbit ears are there in the farm?
(Assuming rabbits have 4 legs and chicken has 2)
160
Given four numbers: 4, a, b, 60. {4, a, b} form a geometric sequence and {a, b, 60} form a arithmetic sequence. What is a+b?
Ans: 48 (a=12 b=36)
What are some factors that can cause economic downturn in an economy?
War, pandemic, natural disaster, political instability
What is the effect of the US-China trade war?
Lower profits for firms // Increase domestic consumption //Lower government income
Simplify the surd: √( 27 + 10√2)
5+√2
Two dice are rolled. What is the probability of the sum being equal to 4?
1/12
The side length of a regular hexagon is 12. What is the area of the hexagon? (Express answer in surds)
Ans: 216√3
Why is hyper-deflation not good?
Discourage consumption//lower profit for firms and income for individuals//unemployment
Hong Kong teachers will receive $20 for marking one full DSE economics paper. What is the disadvantage of this payment method?
low quality of marking
How many sets of positive integer solutions (a,b,c) are there to the equation ab + c = 5?
(a,b,c can be of same value)
8
A rabbit has 15 carrots and would like to eat them in 3 days. Each day, the rabbit must eat at least 1 carrot.
How many different combinations of carrot eaten each day are present?
91
Two pieces of triangular cardboard can be combined to form an n-sided polygon with no overlapping between the pieces. Find the smallest and largest value of n.
3, 6
Assume two firms with similar initial pricing and selling similar products. What would be firm A’s pricing strategy if firm B decides to cut their price, given that there’s free market information to every customer?
Cut price as well
Henry borrowed $2000 at the beginning of 2019. What will be the total amount paid for a loan at a simple interest rate of 8.5% in years which are odd numbers and at an interest rate of 5% p.a. compounded quarterly in even years at the end of 2022?
$2600 (3s.f.)