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Advent calendar 2025
24 December
All 2025 advent puzzles
~
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3 and 5 are both factors of 2025, and 3 and 5 are the only two prime numbers that are factors of 2025.
What is the largest three-digit number that has both 3 and 5 as factors and no other prime numbers as factors?
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The other three digit numbers that have 3 and 5 as factors and no other prime factors are:
3
1
×5
3
= 375
3
2
×5
2
= 225
3
3
×5
1
= 135
3
3
×5
2
=
675
3
4
×5
1
= 405
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differentiation
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christmas
cube numbers
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tournaments
time
cards
digital products
axes
pentagons
clocks
chess
algebra
folding tube maps
dodecagons
indices
determinants
combinatorics
games
cryptic clues
logic
crossnumbers
routes
perfect numbers
trigonometry
area
arrows
parabolas
dominos
multiplication
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polygons
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regular shapes
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ave
consecutive numbers
averages
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geometric means
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remainders
pascal's triangle
squares
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balancing
dice
triangles
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