Tagged: AMC8
Welcome to the Problem Marathon for AMC 8. You can login with google and post your solutions here. The student with most correct solutions will receive an award at the end of the problem marathon.
The question paper of AMC 8, 2024 is available here.
Problem 1
Solution 1-
My idea is to solve it in this manner-
222222-(22222+2222+222+22+2)
I don't care about the number in the brackets but about its unit digit. As 2 is repeating 5 times in the unit digit, it will be 2×5= 10
222222-0= 2 (B)
Problem 2
Solution (The typical method)
$$ \frac{44}{11}+\frac{110}{44}+\frac{44}{1100} $$
We will simplify and get-
$$\frac {4} {1}+ \frac {10} {4}+ \frac {4} {100}$$
$$ = 4+ 2.5+0.04= 6.54 $$(C)
Problem 3
To ease the solution, I have given names to the points
Area of Grey Region= Area of HEFGJI+ Area of AKLMCB
Area of HEFGJI= \( 7^2 \) - \( 4^2 \)
= 49-16= 33
Area of AKLMCB
= \( 10^2 \) - \( 9^2 \)
= 100-81= 19
∴ 33+19=52(E)
Problem 4
The sum from 1 to 9= 45
The square numbers below 45= 1,4,9,16,25 and 36 (Excluding 0)
Now, We can say that the closest 2 square numbers from 45 are 25 and 36
The difference for each is 20 and 9 respectively.
20 is not an element in our set of numbers from 1 to 10
∴ 9 is the number excluded by Yunji (E)