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ITMC 2026 Grade 7 National Preliminary sample-r1 Question 30

ITMC · ITMC 2026 Grade 7 National Preliminary sample-r1

Question 30

For a real number $x$, $[x]$ is the greatest integer not exceeding $x$ (the integer part). The fractional or decimal part is $\{x\}=x-[x]$, so $x=[x]+\{x\}$. Examples: $[3]=3$, $[6.25]=6$, $[-6.25]=-7$, $[22/7]=3$. The source lists: (1) $0<\{x\}<1$ for all real $x$; (2) $\{x\}=0$ exactly when $x$ is an integer; (3) $x-1<[x]\le x<[x]+1$; (4) $[n+x]=n+[x]$ for positive integer $n$ and real $x$; (5) $[-x]=-[x]-1$ if $x$ is not an integer, and $[-x]=-[x]$ if $x$ is an integer. Source correction: property (1) is printed as $0<\{x\}<1$ for all real $x$, contradicting both the definition and property (2) at integers. The correct bound is $0\le\{x\}<1$. The solution uses the definition and this corrected bound.

How many distinct values occur in $\left[\dfrac{1^2}{100}\right],\left[\dfrac{2^2}{100}\right],\ldots,\left[\dfrac{100^2}{100}\right]$?