Find the sum of those integers from 1 to 500 which are multiples of 2

1.	Find the sum of those integers from 1 to 500 which are multiples of 2 or 5
Answer» Sorry there was mistakenSum even numbers from 1to 500 areS2=1/4×500×502=62750......(1)The multiples of 5 not included are5,15,25,.....495If n are terms then 495=5+(n-1)×10490=10n-10. n=50So S5=50/2×(5+495)=25×500=12500Total sum S2+S5==62750+12500=75250\xa0 Multiples of 2 are2,4,6....500S\u200b\u200b\u200b\u200b\u200b\u200b2 =250/2×(2+500)=125×251=31375Multiples of not included are5,15,25,35......495If n are the numbers then495=5+(n-2)×10490+20=5n, n=510/2=255S\u200b\u200b\u200b\u200b\u200b\u200b5\xa0=255/2×(5+595)=600×255/5=76500Total sum =32375+76500=108875\xa0\xa0 12750

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