1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Bond [772]
3 years ago
14

A mother who is 40 years old has a daughter and a son. The son is twice as old as the daugther. In 15 years the sum of all their

ages will be 100 years. How old are the siblings now?
Mathematics
2 answers:
Verizon [17]3 years ago
8 0

Answer:

son = 10

daughter  = 5

Step-by-step explanation:

Let the daughter = d

Let the son =          s

s = 2*d

there ages in 15 years

Mother = 40 + 15 = 55

Son = s + 15

daughter = d + 15

Total: s + 15 + d+15 + 55 = 100    Combine the like terms.

s + d + 85 = 100                            Subtract 85 from both sides.

s + d = 100 - 85

s + d = 15

s = 2*d                                            Substitute for son

2d + d = 15

3d = 15

d = 15/3

d = 5

son = 2*5

son = 10

Check

son = 15 =           25

daughter + 15 =  20

<u>Mother + 15    =   55</u>

Total                   100 just as it should be.

alisha [4.7K]3 years ago
4 0

Answer:

Step-by-step explanation:

Let's call the ages D for daughter and S for son.

We know that the son is twice as old as the daughter, so:

S = 2D

We also know that in 15 years, their ages add up to 100, so:

(40+15) + (S+15) + (D+15) = 100

55 + S + 15 + D + 15 = 100

85 + S + D = 100

S + D = 15

Substituting the first equation:

2D + D = 15

3D = 15

D = 5

Therefore:

S = 2D = 10

The son is 10 and the daughter is 5.

You might be interested in
Find the solution set for this equation M^2-4=0
Helga [31]

Step-by-step explanation:

Hey, there !!

Let's simply work with it,...................

Here, theequation is,

{m }^{2} - 4 = 0

or \:  {m }^{2}  = 4

or \: m  =   +  -  \sqrt{4}

or \: m = + -  \sqrt{ {2}^{2} }

cancelling square and square root we get answer is,

= (+ - 2).

It means the value of m is plus(+) minus(-) 2.

<em>Hope</em><em> </em><em>it helps</em><em>.</em><em>.</em><em>.</em>

5 0
3 years ago
The person pays Social Security 6.2 percent of the first $90,000. Medicare is 1.45 percent of all income. Use the tax tables for
12345 [234]

Answer:

6.2

Step-by-step explanation

I gotta head dont I??

7 0
2 years ago
What is 475% of 9.2?
coldgirl [10]
To find this, multiply 9.2 by the decimal form of the percent (4.75). The answer is 43.7
7 0
3 years ago
Read 2 more answers
Use the discriminant to describe the roots of each equation. then select the best description. x^2 - 4x + 4 = 0
Vaselesa [24]
B is the answer to the question
3 0
3 years ago
Jose tosses a fair coin 2 times. What is the probability it will land on heads two times in a row?
Umnica [9.8K]
1/2 is the answer. hope this helps
3 0
3 years ago
Read 2 more answers
Other questions:
  • The width of a computer monitor is 1.25 times its height. Find the height of the computer monitor when the height is x and the w
    8·1 answer
  • Find the lengths, if needed round to the nearest tenth
    12·1 answer
  • Which statements are true about triangle ABC and its translated image, A'B'C'? Check all that apply.
    7·2 answers
  • How do i show that this equation equals this?
    9·1 answer
  • Can 927/100 be simplified
    11·1 answer
  • Convert these decimals into fractions 0.49 and 4.542
    13·1 answer
  • Help me with 6 and 7 please
    13·1 answer
  • What is 2+2-2*2/2= to
    10·2 answers
  • SOMEONE HELP ME PLEASE
    10·2 answers
  • Please helppp!! i will give you brainliest, helpp!!
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!