Base case: if <em>n</em> = 1, then
1² - 1 = 0
which is even.
Induction hypothesis: assume the statement is true for <em>n</em> = <em>k</em>, namely that <em>k</em> ² - <em>k</em> is even. This means that <em>k</em> ² - <em>k</em> = 2<em>m</em> for some integer <em>m</em>.
Induction step: show that the assumption implies (<em>k</em> + 1)² - (<em>k</em> + 1) is also even. We have
(<em>k</em> + 1)² - (<em>k</em> + 1) = <em>k</em> ² + 2<em>k</em> + 1 - <em>k</em> - 1
… = (<em>k</em> ² - <em>k</em>) + 2<em>k</em>
… = 2<em>m</em> + 2<em>k</em>
… = 2 (<em>m</em> + <em>k</em>)
which is clearly even. QED
It can be helpful to remember that "%" is just a shorthand way to write "/100" (divided by 100, or per 100, or per cent). ("Cent" is often used to refer to 100 or 1/100. A "cent" is 1/100 of a dollar, or 1/100 of an acre, for example. A <em>cent</em>ury is 100 years.)
Make the denominator of your fraction be 100. Multiply numerator and denominator by 20/20.
(2/5)×(20/20) = 40/100 = 40%
You can also get there via decimals.
... 2/5 = 0.4 = 0.40 (40 hundredths) = 40/100 (40 hundredths) = 40%
Or, you can multiply by 100%.
... (2/5)×(100%) = (200/5)% = 40%
4232 divided by 18 equals 235.1
The -2 has a multiplicity of 2
Since the order of (x+2) is squared, i.e. power is 2
Answer:
Dan can buy 5 bags for 15 dollars
Step-by-step explanation:
divide 15 and 3 it will equal 5