2018 - JAMB Mathematics Past Questions and Answers - page 3
If the simple interest on a sum of money invested at 3% per annum for 2\(\frac{1}{2}\) years is N123, find the principal.
A machine valued at N20,000 depreciates by 10% every year. What will be the value of the machine at the end of two years?
10% depreciation at the end of first year (100-10%) = 90% of 20000
= \(\frac{90}{100}\) x 20000 =18000
At the end of second year, its value = 90% of 18000
= \(\frac{90}{100}\) x 18000 = ₦16,200
The table shown gives the marks scored by a group of student in a test. Use the table to answer the question given.
| Mark | 0 | 1 | 2 | 3 | 4 | 5 |
| Frequency | 1 | 2 | 7 | 5 | 4 | 3 |
What is the median mark?
Total frequency = 1 + 2 + 7 + 5 + 4 + 3 = 22
Median:
= \(\frac{Nth}{2}\)
term = \(\frac{22th}{2}\) = 11th term
Going in ascending order, 11th term is 3, going in descending order 11th term is 3
Median = 3 + \(\frac{3}{2}\) = \(\frac{6}{2}\) = 3
The table shown gives the marks scored by a group of student in a test. Use the table to answer the question given.
| Mark | 0 | 1 | 2 | 3 | 4 | 5 |
| Frequency | 1 | 2 | 7 | 5 | 4 | 3 |
What is the probability of selecting a student from the group that scored 2 or 3
A boy walks 800m in 20 minutes. Calculate his average speed in Km/H
A car uses one litre of petrol for every 14km. If one litre of petrol cost N63.00, how far can the car go with N900.00 worth of petrol?
1litre cost ₦63
₦900 is the cost of \(\frac{900}{63}\) litres
= 14.2857litres of petrol
nbsp; The car uses 1 litre for 14km
So 14.2857 litres will be used for (14.2857 x 14)
= 200km
In the diagram, GI is a tangent to the circle at H. If EF||GI, calculate the size of ∠EHF
How many times, correct to the nearest whole number, will a man run round a circular track of diameter 100m to cover a distance of 1000m?
Perimeter of circle = 2πr = πD (note D = 2r)
Where r is radius and D is the diameter
So perimeter = \(\frac{22}{7}\) x 100
= 314.2857m
To cover a distance of 1000m, he is going to round the circular track for \(\frac{1000}{314.2857}\) = 3.18
That is, at the number 4 round he is going to cover up to 1000m
Use the cummulative frequency curve to answer the question. Estimate the median of the date represented on the graph
Use the cummulative frequency curve to answer the question. What is the 80th percentile?