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(Q). Find the first two non zero digit i.e. FTNZD in 100×101×102×………..till 100 terms.
Solution:-

\frac{{199!}}{{99!}}
So we have to find FTNZD in \left( {\frac{{199!}}{{99!}}} \right)
first find FTNZD(199!) ⇒ 

Remainder5555199397104421Q₁ = Uₜ(199×198×197×196) = 24Q₂ = Uₜ(39×38×37×36) = 24Q₃ = Uₜ(7×6) = 42Q₄ = Uₜ(1) = 01H = 47

∴ FTNZD(199!) = 12⁴⁷ × Uₜ(24×24×42×1)
                             = (2²×3)⁴⁷ × Uₜ(76×42)
                             = 2⁹⁴ × 3⁴⁷ × 92
                             = (2²⁰)⁴ × 2¹⁴ × (81)¹¹ ×27 ×92
                             = 76 × 84 × 81 × 27 × 92
                             = 36

Now to find FTNZD(99!)

Remainder555 991930443Q₁ = Uₜ(99×98×97×96) = 24Q₂ = Uₜ(19×18×17×16) = 24Q₃ = Uₜ(3×2×1) = 06H = 22

∴ FTNZD(99!) = 12²² × Uₜ(24×24×6)
                           = (2²×3)²² × Uₜ(76×6)
                           = 2⁴⁴ × 3²² × 56
                           = (2²⁰)² × 2⁴ × (81)⁵ × 3² × 56
                           = 76 × 16 × 01 × 9 × 56
                           = 64

Now 199! has 47 trailing zeros & 99! has 22 trailing zeros
∴ \frac{{199!}}{{99!}} will have 47 – 22 = 25 trailing zeros
So FTNZD of \left( {\frac{{199!}}{{99!}}} \right) will be the division of FTNZD of 199! & FTNZD of 99!
∴FTNZD\left( {\frac{{199!}}{{99!}}} \right) = \frac{{FTNZD(199!)}}{{FTNZD(99!)}}\frac{{36}}{{64}}
From given options Uₜ(64×24) = 36

Hence Answer = 24     option (iii) is correct.