Verified Solution • 2025–26 Session moderate

QJEEM25Ma1c56: JEE Main 2025 Mathematics - Class 11 JEEM25Ma1c56 Solution: The number of natural numbers, between 212 and 999, such that…

The number of natural numbers, between 212 and 999, such that the sum of their digits is 15, is _______.

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xamp;yamp;z\begin{array}{|c|c|c|}\hline \mathrm{x} & \mathrm{y} & \mathrm{z} \\\hline\end{array}

Let x=2⇒y+z=13\mathrm{x}=2 \Rightarrow \mathrm{y}+\mathrm{z}=13

(4,9),(5,8),(6,7),(7,6),(8,5),(9,4),→6(4,9),(5,8),(6,7),(7,6),(8,5),(9,4), \rightarrow 6

Let x=3→y+z=12x=3 \rightarrow y+z=12

(3,9),(4,8),……..,(9,3)→7(3,9),(4,8), \ldots \ldots . .,(9,3) \rightarrow 7

Let x=4→y+z=11x=4 \rightarrow y+z=11

(2,9),(3,8),………,(9,1)→9(2,9),(3,8), \ldots \ldots \ldots,(9,1) \rightarrow 9

Let x=5→y+z=10x=5 \rightarrow y+z=10

(1,9),(2,8),……..,(9,1)→10(1,9),(2,8), \ldots \ldots . .,(9,1) \rightarrow 10

Let x=6→y+z=9x=6 \rightarrow y+z=9

(0,9),(1,8),……..,(9,0)→9(0,9),(1,8), \ldots \ldots . .,(9,0) \rightarrow 9

Let x=7→y+z=8\mathrm{x}=7 \rightarrow \mathrm{y}+\mathrm{z}=8

(0,9),(1,7),……..,(8,0)→9(0,9),(1,7), \ldots \ldots . .,(8,0) \rightarrow 9

Let x=8→y+z=7x=8 \rightarrow y+z=7

(0,7),(1,6),……..,(7,0)→8(0,7),(1,6), \ldots \ldots . .,(7,0) \rightarrow 8

Let x=9→y+z=6x=9 \rightarrow y+z=6

(0,6),(1,5),………,(6,0)→7(0,6),(1,5), \ldots \ldots \ldots,(6,0) \rightarrow 7

Total =6=7+8+9+10+9+8+7=64=6=7+8+9+10+9+8+7=64

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