Respuesta :

Multiplos de 2 ...100,102,............302.....( 302-100):2+1=101+1=102 numbers
Multiplos de 5.......100,105,110.....300 .......(300-100):5+1=40+1=41 numbers 
Multiplos de 7.........105, 112,119....301.......(301-105):7+1=28+1=29 numbers
Multiplos de 2 si 5  100,110,120.......300......(300-100):10+1=21 numbers
Multiplos de 2 si 7  112, 126,............294.......(294-112):14+1=14 numbers
Multiplos de 5 si 7  105, 140..............280......(280-105):35+1=6 numbers

n=102+41+29-(21+14+6)=172-41=131 numbers

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