Answer:
She paid 9% of sales tax
Step-by-step explanation:
The sale price of diamond = $375
Let x be percent of sales tax
So, amount of tax =
So, Amount including tax = 375+3.75x
We are given that Bethany paid $408.75 for a pair of diamond stud earrings.
So, 375+3.75x=408.75
3.75x=408.75-375
x=9
Hence She paid 9% of sales tax
Answer:
no, depends on what the ball costs but no because its .25 (meaning cents) not 25.00 (meaning dollars)
Step-by-step explanation:
You can make a start by putting together an expression for the sum of the even integers between 1 and k inclusive.
Let S be the sum of the even integers between 1 and k inclusive.
Then:
<span><span>S=2+4+6+⋯+(k−2)+k</span></span>
As k is even, you can say r = 2k and so:
<span><span>S=2(1+2+3+⋯+(r−1)+r)</span></span>
<span>Now the sum of the first </span><span>r</span><span> numbers is well-known, it's the </span><span>r</span>th triangle number and we have:
<span><span>1+2+3+⋯+(r−1)+r=<span><span>r(r+1)/</span>2</span></span></span>
<span>Now we can keep it simple and say </span><span><span>2k=4r </span></span><span>and so:</span>
<span><span>S=2(1+2+3+⋯+(r−1)+r)=4r=2<span><span>r(r+1)</span>2</span>=r(r+1)</span></span>
<span>So you can build a quadratic in </span><span>r</span><span> and so get </span><span>k.</span>
Let x be the amount invested at 6%
840 = 0.06x + 0.075(2x)
840 = 0.06x + 0.15x
840 = 0.21x
x = 840/0.21
x = 4000
Therefore, she invests $4000 at 6% and $8000 at 7.5%