Please help confused with half life /compound interest problems1. Fermium-252 decays in 10 minutes to 76.1% of its original
mass. Find the half-life of fermium-252.
2. How long do you have to wait until 15mg of beryllium-7 have
decayed to 4mg, if the half-life of beryllium-7 is 53.12 days?

Answers

Answer 1

Answer: Half life means only half of matter is left, which means half is decayed/radiated.
Formula for half life is
t/2 = [(elapsed time)*(log2)]/[log(beginning amount/ending amount)]
1. t/2 = [(10)*(log2)]/[log(100/76.1)] = 25.378 minutes.
t/2 = [10 * 0.301]/[log 1.314] = [3.01]/[0.1186] = 25.378
2. 53.12 = [(T)*(log2)]/[log(15/4)], on solving we get, T = 101.29 days
53.12 = [T * 0.301]/[log 3.75] = [0.301 * T]/[0.574],
T = [53.12 * 0.574]/[0.301] = [30.49]/[0.301] = 101.29

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What multiplies to 0 and adds to 8

Answers

Anything multiplied by 0 will always equate to 0.

That means the two numbers are 8 and 0.

(0 × 8 = 0)
(0 + 8 = 8)

Which quadratic function has one real solution?A.0 = 2(x + 7)(x – 5)
B.0 = (x – 3)(x – 3)
C.0 = 2.4(x – 2)(x + 2)
D.0 = (x – 2)(x – 1)

Answers

Hello,

B; (x-3)² solution 3 multiplicity 2
others have two roots.

Answer:

The answer is B (0 = (x – 3)(x – 3))

HELP PLEASE !!!!!!!!!!!!A ﬂorist has to order roses and carnations for Valentine’s day. The ﬂorist needs to decide how many dozen roses and carnations should be ordered to obtain a maximum proﬁt.

• Roses: The ﬂorist’s cost is $20 per dozen;
the proﬁt over cost is $20 per dozen.
• Carnations: The ﬂorist’s cost is $5 per
dozen; the proﬁt over cost is $8.
• The ﬂorist can order no more than 50 dozen
ﬂowers.
• A minimum of 30 dozen carnations must be
ordered.
• The ﬂorist cannot order more than $660
worth of roses and carnations.

A.) How many dozen roses should the ﬂorist order? Answer in units of doz

B.) How many dozen carnations should the ﬂorist order? Answer in units of doz

Answers

30 dozen carnations.
20 dozen roses.
This means she spends 550, but makes 640.
I hope this is right?

The component of a along b is root 3 times that of the component of b along a. Then, is a : b?

Answers

Answer:

$√(3) :1$

Step-by-step explanation:

Given:

$\vec{a}_{\vec{b}}=√(3)* \vec{b}_{\vec{a}}$

$|\vec{a}|cos\theta=√(3) *|\vec{b}|cos\theta$

$|\vec{a}|=√(3) *|\vec{b}|$

$|\vec{a}|:|\vec{b}|=√(3) : 1$

It takes 32 minutes for 3 people to paint 4 walls. How many minutes does it take 4 people to paint 7 walls?

Answers

we order these data:

32 minutes------------------------3 people------------------4 walls
x--------------------------------------4 people------------------7 walls
The minutes and the people are variables inversely proportional , therefore, we multiply in parallel
32 minutes*3 people=x*4 people

The minutes and the walls are variables directly proportinal; therefore, we multiply cross.
32 minutes*7 walls=x*4 walls

Therefore:
32 minutes*3 people*7 walls=x*4 people*4 walls
x=(32 minutes*3 people*7 walls) / (4 people* 4 walls)
x=42 minutes.

Answer: the time will be 42 minutes.

Answer:

Step-by-step explanation:

that is the answer on khan academy

hope that helped!

a thanks would be appreciated! ;)

What is the completely factored form of the expression 16x2 + 8x + 32?

Answers

8 is a common factor for all coeficients so we factor it out first: 8(2x^2 + x + 4). Now we have to check can we factor the quadratic equasion in the brackets to linear factors. To do that we need to check is the discriminant D=b^2 - 4ac > 0 where a=2, b=1 and c=4. When we insert our numbers, we get: D= -31. We see that D < 0 so 8(2x^2 + x + 4) is the completely factored form.

Answer:

8(2x^2 + x + 4)

Step-by-step explanation:

edge2020

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during a basketball game, your team scored three times as many 2-point field goals than it did 3-point field goals, and scored a total of 90 points. How many field goals did your team score?

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