Grading: platform starts at 0; Q1–15: 2 points each, Q16–25: 4 each; wrong/blank: 0; maximum 70. Official reference starts at 15; Section A +2/−1/0 and Section B +4/0/0 for correct/wrong/blank; maximum 85. Time: 90 minutes (official-reference default).
Emma earns $a$ dollars per hour for the first 6 hours of her shift and $b$ dollars per hour for each hour after that. If she works 12 hours in one shift, what is her average hourly wage?
Tom spent 450 dollars on clothes and 40% of his remaining money on school stationery. He then had 26.25% of his original money left. How much did he have at first?
A square has side length 84 cm. Three semicircles are drawn inside it, with three sides of the square as diameters, as shown. Find the shaded area in $\mathrm{cm}^2$. Use $\pi=\frac{22}{7}$.
In square $ABCD$, $E$ and $F$ lie on $AD$ and $CD$ respectively, with $3DE=3FC=AB$. Segments $BF$ and $CE$ meet at $G$. The square has area $140\ \mathrm{cm}^2$. Find the area of quadrilateral $EDFG$.
How many triangles are in the figure below? Count triangles of every size whose sides lie entirely on drawn straight segments.
Answer format: enter one whole number without units. The source answer sheet uses four digits with leading zeros if needed; ordinary numeric entry is used here.
A four-digit number has four different digits whose product is 810. What is the greatest such number?
Answer format: enter one whole number without units. The source answer sheet uses four digits with leading zeros if needed; ordinary numeric entry is used here.
The four-digit number 1120 is divisible by the sum of its digits, $1+1+2+0=4$. What is the greatest four-digit number divisible by the sum of its digits?
Answer format: enter one whole number without units. The source answer sheet uses four digits with leading zeros if needed; ordinary numeric entry is used here.
The operation $\triangle$ is illustrated by $3\triangle3=2+3+4$, $5\triangle2=4+5$, and $9\triangle6=8+9+10+11+12+13$. If $x\triangle12=2022$, find $x$.
Convention: the second input is the number of consecutive terms, beginning one below the first input.
Answer format: enter one whole number without units. The source answer sheet uses four digits with leading zeros if needed; ordinary numeric entry is used here.
The 2022nd term of the sequence below, reduced to lowest terms, is $a/b$ with $\operatorname{HCF}(a,b)=1$. Find $a+b$.
Pattern convention: for each denominator $n=2,3,4,\ldots$, list numerators $1,2,\ldots,\lfloor n/2\rfloor$ in order. Keep every displayed position even when two fractions have the same value.
Answer format: enter one whole number without units. The source answer sheet uses four digits with leading zeros if needed; ordinary numeric entry is used here.