Berikut ini adalah soal beserta kunci jawaban Fermat Mathematic Olympiad (FMO) 2021 grade 9 (Sc: Halaman facebook FMO)

1. Refer to the pattern below. Find the missing figure.

A.

B.

C.

D.

E.

2. Ashley arranges five puzzle pieces below to make one mathematical expression. Find the greatest value that Ashley can create.

A. 5

B. 10

C. 100

D. 101

E. 110

3. Emma and Lilly have some cards, each of which is one-digit prime number. They combine cards to form 2 two-digit prime numbers. Given that Emma’s number is the smallest possible value and Lilly’s number is the greatest possible value. Find their sum.

A. 84

B. 107

C. 110

D. 86

E. 96

4. Amy glues 6 steel wires, each of length 20cm to create the pyramid below. Starting at one vertex, she decorates it with black beads along every edge at 2cm intervals. When she completes, how many beads has she used?

A. 60

B. 56

C. 54

D. 58

E. 52

5. In May 2021, two teams A and B produced 720 machine parts altogether. In June 2021, since team A produced more than last month 15% and team B produced the same, at the end of the month both groups produced 765 machine parts. How many machine parts can be produced in May 2021 by team B?

A. 300

B. 345

C. 336

D. 400

E. 420

6. While a pile of seven chairs is 1.44 meters, a pile of ten chairs is 1.56 meters. Find the height of one chair.

A. 1.2m

B. 1.1m

C. 1.3m

D. 1.4m

E. None of the above

7. In front of Graham’s Bicycle Bazaar there are some unicycles, some bicycles and some tricycles. Lucy sees that there are seven saddles in total, thirteen wheels in total and more bicycles than tricycles. How many unicycles are there?

A. 1

B. 2

C. 3

D. 4

E. 5

8. Lucy folds the net below to get a paper house. Which figure does Lucy’s house look like?

A.

B.

C.

D.

E. None of the above

9. There are some students who participate an Olympiad Mathematic Test, each of them has to do 10 math problems. The points are given as follows. The contestants get 2 points for each correct answer, 1 point for each blank answer and 0 point for each wrong answer. At least how many students are there to ensure that two of them get the same score?

A. 11

B. 12

C. 20

D. 21

E. 22

10. Three isosceles triangles and an equilateral triangle are

combined to form a square as the figure below.

Calculate the angle \(AEB\) .

A. \(120^0\)

B. \(130^0\)

C. \(140^0\)

D. \(150^0\)

E. \(160^0\)

11. Rachel draws a \(5\times 5\) table. She colors each cell with one of 4 colors: Red, Blue, Yellow and Green so that any two cells with the same vertex must be different. Unfortunately, her younger brother erased most of the color as the picture below.

Which color can the cell “X” be painted by Rachel?

A. Only blue

B. Only green

C. Only red

D. Red or yellow

E. Yellow or green

12. There is a spider sitting in the middle of the red wall in the bedroom. A butterfly is resting at the top left corner of the window which is placed in the middle of the opposite wall. Given that the cubic bedroom has side length of 2.8m and the square window has a side length of 1.2m. What is the shortest distance the spider would have to crawl on the wall to catch the butterfly given that his path must be parrallel to one of the side?

(*Image is for illustrative purposes*)

A. 5.2m

B. 5.5m

C. 5.6m

D. 6m

E. 5m

13. The velocity of a train is recorded in the line graph below. Find its velocity at 7.4

seconds.

A. 44m/s

B. 45m/s

C. 46m/s

D. 47m/s

E. None of the above

14. There is a pile of rice sacks. The weight of three lightest sacks is 21% of the whole pile. The weight of four heaviest sacks is \(\frac{3}{5}\) of the whole pile. How many rice sacks are there in the pile?

A. 7

B. 8

C. 9

D. 19

E. 26

15. A rectangular paper with dimension 25cm x 20cm is folded so that the vertex B lies on the side AD as the figure below. Find the area of the paper after being folded.

A. 343 \(cm^2\)

B. 343.75 \(cm^2\)

C. 344 \(cm^2\)

D. 343.5 \(cm^2\)

E. None of the above

16 In a camp trip, the students bring two wooden sticks of length 2.5m to build the frame of the tent gate as the figure below. Since Andy sees a heavy cubic box on the ground, he manages to push it through the gate into the tent. Find the maximum volume of the box in \(m^3\).

kunci jawaban: