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Help please with this maths I need to check it it’s right

Help please with this maths I need to check it it’s right-example-1
User SuperGeo
by
7.6k points

2 Answers

5 votes

Answer:9999

I hope it is helpful:)

Explanation:

we can see 99 is 100-1 and 101 is 100+1

we can rewrite this as,

99*101=(100-1)(100+1)

let's use short mltiplication formula,


a^(2)-b^(2)=(a-b)(a+b)\\(100-1)(100+1)=100^(2)-1^(2)=10000-1=9999

User Phate P
by
7.4k points
4 votes

Answer:

9999

Explanation:

99x10=990

99x1=99

9999

User Ove Stoerholt
by
7.7k points