IB Maths Applications & Interpretation — Interactive Practice Paper 2
Paper 2 is the calculator-required paper — real-world modelling, financial mathematics, regression and applied calculus. Grab your GDC (Casio fx-CG50 / TI-84) and go. Two modes: instant per-part feedback, or full timed exam.
Elena makes a deposit of $\$400$ at the end of each month into a savings annuity paying a nominal annual rate of $4.8\%$, compounded monthly. She does this for 10 years.
(a) Using your GDC, calculate the total future value of the account after 10 years. Give your answer to the nearest cent. [3]
Casio fx-CG50 · MENU F · CMPD: $N=120, I\%=4.8, PV=0, PMT=-400, P/Y=12, C/Y=12$.
(b) Calculate the total amount Elena deposited from her own pocket. [2]
(c) Calculate the total interest Elena earned over the 10 years. [2]
Two schools are represented by points $A(2, 20)$ and $B(14, 24)$ on a map. A road, represented by line $R$ with equation $-x + y = 4$, passes near the schools. A town planner wants to place a bus stop on the road so it is exactly the same distance from both schools.
(a) Find the gradient of $[AB]$. [1]
(b) Find the midpoint of $[AB]$. Give as $(x, y)$. [1]
(c) Find the equation of the perpendicular bisector of $[AB]$ in the form $y = mx + c$. Give $c$ to the nearest integer. [3]
$m_\perp = -3$; passes through midpoint.
(d) Find the $x$-coordinate of the bus-stop location (intersection of $R$ with the perpendicular bisector). [2]
The mean of five distinct positive integers is $8.5$.
(a) Find the sum of these five integers. [1]
(b) A sixth integer, $x$, is added to the data set. The new mean of all six values is $9$. Find $x$. [2]
(c) Class A (20 students) achieved a mean score of $65$. Class B (30 students) achieved a mean score of $80$. Calculate the combined mean of all 50 students. [3]
Bivariate Data — regression line & percentage error
An environmentalist models the relationship between the distance from a highway ($d$, in metres) and the concentration of a pollutant ($C$, in parts per million). The regression line is $C = -0.04d + 8.5$.
(a) Estimate the concentration at $d = 50$ m. [2]
(b) The actual measured concentration at $50$ m was $7.1$ ppm. Calculate the percentage error of the estimate, to 3 significant figures. [3]