Zoe and Hannah share tips in the ratio 3:7 . Last week Zoe received £24 . How much did Hannah receive last week?

An actor invests some money at 7%, and $24000 more than four times the amount at 8%. The total annual interest earned from the i

natita [175]

Answer:

$70,000 at 7%
$304,000 at 8%

Step-by-step explanation:

Given:

Total interest earned on two investments is $29,220.

An amount is invested at 7%.

$24,000 more than 4 times that amount is invested at 8%.

Find:

The amount invested at each rate.

Solution:

Our strategy will be to define a variable representing the amount invested at 7%, use that variable to write an expression for the amount invested at 8%, then write an equation for the total return on the investments.

Let x represent the amount invested at 7%. Then (24,000+4x) will be the amount invested at 8%. The total interest earned will be ...

interest on 7% account + interest on 8% account = total interest

0.07x + 0.08(24000+4x) = 29220

0.39x + 1920 = 29220 . . . . . . . . . . . simplify

0.39x = 27300 . . . . . . . . . . . . . . . . . .subtract 1920

x = 27300/0.39 = 70000 . . . . . . . . . divide by the coefficient of x

24,000 +4x = 24,000 +280,000 = 304,000 . . . . amount invested at 8%

He invested $70,000 at 7% and $304,000 at 8%.

Check

The answer must satisfy ...

7% interest + 8% interest = 29,220

0.07×70,000 +0.08×304,000 = 4,900 +24,320 = 29,220 . . . . as required

_____

Comment on 6-step method

We have tried to hit the highlights. Your steps appear to be ...

Identify the given information (Given)
Identify the question you are asked to answer (Find)
Identify the useless information in the problem statement (is none)
Decide on a strategy. Make a model or drawing. (model equation shown)
Solve and show work (Solution)
Explain why the answer makes sense (Check)

6 0

3 years ago

Mai wants to make an open top box by cutting out corners of a square piece of cardboard and folding up the sides. The cardboard

Bumek [7]

Answer:

$V(x)=(4x^{3}-40x^{2}+100x)\ cm^3$

The domain for x is all real numbers greater than zero and less than 5 com

Step-by-step explanation:

The question is

What is the volume of the open top box as a function of the side length x in cm of the square cutouts?

see the attached figure to better understand the problem

Let

x -----> the side length in cm of the square cutouts

we know that

The volume of the open top box is

$V=LWH$

we have

$L=(10-2x)\ cm$

$W=(10-2x)\ cm$

$H=x)\ cm$

substitute

$V(x)=(10-2x)(10-2x)x\\\\V(x)=(100-40x+4x^{2})x\\\\V(x)=(4x^{3}-40x^{2}+100x)\ cm^3$

Find the domain for x

we know that

$(10-2x) > 0\\10> 2x\\ 5 > x\\x < 5\ cm$

so

The domain is the interval (0,5)

The domain is all real numbers greater than zero and less than 5 cm

therefore

The volume of the open top box as a function of the side length x in cm of the square cutouts is

$V(x)=(4x^{3}-40x^{2}+100x)\ cm^3$

5 0

3 years ago

In 1928, when the high jump was first introduced as a women's sport at the Olympic Games, the winning jump for women was 70.0 in

sveta [45]

Answer: year 2194

Explanation:

1) Model the jump of the women:

i) initial jump = 70.0 in

ii) increase rate = 0.48% per year

iii) equation: h = 70.0(1 +0.0048)ⁿ

2) Model the jump of the men:

i) initial jump 86.5 inches.

ii) increase rate, 0.4%.

iii) equation: h = 86.5 (1 + 0.004)ⁿ

3) Equal the two equations (h = h) to find when the jumps will be equal:

i) 70.0(1 +0.0048)ⁿ = 86.5 (1 + 0.004)ⁿ

ii) 70.0(1.0048)ⁿ = 86.5 (1.004)ⁿ

ii) [1.0048ⁿ / 1.004ⁿ] = 86.5/70.0

iii) [1.0048/ 1.0040]ⁿ = 86.5/70.0

iv) n log (1.0048 / 1.0040) = log ( 86.5/70)

v) n = log (86.5/70) / log (1.0048/1.0040) ≈ 266

3) year = 1928 + 266 = 2194

That is in the year 2194

8 0

3 years ago

Read 2 more answers

Julie wants to buy tulip bulbs to plant. Each bulb costs $0.50 plus a one-time $4.50 shipping cost. She has $22 to spend.

kumpel [21]

Answer:

0.50 x 4.50 = 69.42.00 and 22 = 47.420.00

Step-by-step explanation:

47.420.00

7 0

3 years ago

5. A video store charges a monthly

Rasek [7]

Answer: 8 movies

12 + 1.50x = 3x

Move the variables to one side

12 = 1.50x

Isolate x

8 = x

Check:

3(8)= 24

12.00 + 1.50(8) = 24

8 0

3 years ago