Systems of linear equations
Practice section 3 of 4
Questions 13–18 in this collection
Practice questions
Review practice · 1 of 6
Juice mixtures: conserve volume and each ingredient
Three brands of apple juice, A, B and C, each contain a certain percentage of pure juice and some artificial flavouring. The breakdown of the amount of juice and flavouring for each brand is summarised in the table below.
| A | B | C | |
|---|---|---|---|
| Pure juice (%) | 20 | 70 | 40 |
| Artificial flavouring (%) | 0.5 | 0.8 | 0.7 |
How many litres of each brand should be mixed to produce 300 litres of juice with 41.1% pure juice and 0.647% artificial flavouring? [3]
[2016/ACJC/Promo/1]
CJC · Review Problems · Question 4
Solution
Review practice · 2 of 6
Basketball: distinguish attempts, successes and points
In basketball, points are scored by a successful free throw or a field goal. A successful free throw is worth 1 point while a field goal is worth either 2 or 3 points. An attempt can either be a free throw attempt or a field goal attempt.
In the recently concluded basketball season, Stephen had 1695 attempts in total. 60% of these attempts were successful and he scored a total of 1917 points. 40% of his successful free throws and 25% of his field goal points were scored during the second half of the season, where Stephen scored a total of 534 points.
Calculate the number of 2-point field goals during the season. [5]
[2016/NJC/Promo/3]
CJC · Review Problems · Question 5
Solution
Review practice · 3 of 6
Recover a rational curve from points and a gradient
The equation of a curve is given by , where are constants. The gradient of at the point is 3. It is also given that passes through the point . Find the values of . Hence state the equations of the asymptotes of . [4]
[2016/YJC/Promo/10(a)]
CJC · Review Problems · Question 6
Solution
Review practice · 4 of 6
A cubic determined by two points and two stationary inputs
The graph of , where is a cubic polynomial, passes through the points , and has two stationary points at and .
Find the equation of the curve and hence find its -intercept. [5]
[2013/CJC/Promo/3]
CJC · Review Problems · Question 7
Solution
Review practice · 5 of 6
Use a remainder and a stationary point as constraints
A cubic polynomial leaves a remainder of 52 when divided by . Given that the curve with equation passes through the point and has a stationary point at , find . [4]
[2018/EJC/Promo/2]
CJC · Review Problems · Question 8
Solution
Review practice · 6 of 6
Brick orders: distinguish a fixed-profit system from cost minimisation
A brick manufacturer has a depot with a stock of 30 000 bricks. He receives orders from three builders P, Q and R for a total of 30 000 bricks and the total order from builders P and R is twice that of builder Q.
(a) If the profit earned from each brick is $3 and the manufacturer earns $9 600 more in profit from builder R compared to builder P, find the number of orders from each builder. [4]
(b) Instead of using the information in part (a), it is now given that the cost of transporting each brick to builders P, Q and R from the depot is $0.04, $0.02 and $0.03 respectively. If there is a minimum order of 1000 bricks from each builder, what are the orders that the manufacturer should accept so as to keep the cost of transportation a minimum? [3]
[2016/MI/PU1/Promo/3]
CJC · Review Problems · Question 9