Answer:
x = 3.464
Step-by-step explanation:
7x^2 - 84 = 0
7x^2 = 84
x^2 = 12
x= 3.464
Half of 2/3 is:
This means that 1/3 was left. This also means that they ate 1/3 of the lasagne.
Model diagram can be seen in attachment.
<span>We are not told how often the interest is compounded, so assuming it is <em /><u><em>compounded yearly</em></u>, you need to keep $9.99 in the account to pay the fee.
<u><em>Explanation: </em></u>
Compound interest follows the formula A=p(1+r)^t,
where:
A is the total amount in the account,
p is the amount of principal,
r is the interest rate as a decimal number,
and t is the number of years.
<u>For our problem: </u>
A = 9.99,
p is unknown,
r = 0.018% = 0.00018,
and t=1.
<u>This gives us: </u>
9.99=p(1+0.00018)^1;
9.99=p(1.00018).
<u>Divide both sides by 1.00018: </u>
9.99=p.</span>
<span>Look at your table for a Z value of 1.55. The numbers on the far left column are your z values. See the 1.5 row, then move over to the 0.05 column to make it 1.55.
You'll see 0.9394.
That's the area under the normal curve from 1.55 to negative infinity.
But you wanted the area under the curve greater than 1.55.
Take 1-0.9394=0.0606.
You subtract from 1 because you know that the area under the whole curve is 1, so it gives you the area you need.</span>
