All categories

2 years ago

James is five years older than David. The sum of their ages is 89. How old is David?

Mathematics

2 answers:

valentina_108 [34]2 years ago

7 0

Answer:

If james is 5 years old than David then

subtract 5 from their sum of age
Then divide the answer with 2
There's the age of David

Ans is 42

Dafna1 [17]2 years ago

5 0

Answer:

Let David's age be x years

=> James' age = x+5 years

David + James = 89

=> x + x+5=89

=> 2x=84

=> x=84/2=42 years

David's age is 42 years

You might be interested in

How do ypu slove dis? y^2(q-4) - c(q - 4)

Annette [7]

y2(q-4)-c(q-4) Final result : (q - 4) • (y2 - c)

Step by step solution :Step 1 :Equation at the end of step 1 : ((y2) • (q - 4)) - c • (q - 4) Step 2 :Equation at the end of step 2 : y2 • (q - 4) - c • (q - 4) Step 3 :Pulling out like terms :

3.1 Pull out q-4

After pulling out, we are left with :
(q-4) • ( y2 * 1 +( c * (-1) ))

Trying to factor as a Difference of Squares :

3.2 Factoring: y2-c

Theory : A difference of two perfect squares, A2 - B2 can be factored into (A+B) • (A-B)

Proof : (A+B) • (A-B) =
 A2 - AB + BA - B2 =
 A2 - AB + AB - B2 =
 A2 - B2

Note : AB = BA is the commutative property of multiplication.

Note : - AB + AB equals zero and is therefore eliminated from the expression.

Check : y2 is the square of y1 

Check : c1 is not a square !!
Ruling : Binomial can not be factored as the difference of two perfect squares

Final result : (q - 4) • (y2 - c)

4 0

3 years ago

Refer to the previous exercise. The researchers wanted a sufficiently large sample to be able to estimate the probability of pre

Maru [420]

Answer:

The large sample n = 117.07

Step-by-step explanation:

Step(i):-

Given that the estimate error (M.E) = 0.08

The proportion (p) = 0.75

q =1-p = 1- 0.75 =0.25

Level of significance = 0.05

Z₀.₀₅ = 1.96≅ 2

Step(ii):-

The Marginal error is determined by

M.E = $\frac{Z_{0.05} \sqrt{p(1-p)} }{\sqrt{n} }$

$0.08 = \frac{2 X \sqrt{0.75(1-0.75)} }{\sqrt{n} }$

Cross multiplication , we get

$\sqrt{n} = \frac{2 X \sqrt{0.75(1-0.75)} }{0.08 }$

√n = $\frac{2 X0.4330}{0.08} = 10.825$

squaring on both sides , we get

n = 117.07

Final answer:-

The large sample n = 117.07

6 0

2 years ago

which three numbers make a right triangle the square root of 4 the square root of 5 the square root of 9 + square root of 6 the

statuscvo [17]

Please, group your sets of numbers, using { } notation or at least semicolons ( ; ). Thanks.

Looking at what I think is your first set: { sqrt(4), sqrt(5), sqrt(16) }

Square each of these and then subst. the results into the Pythagorean Theorem:

{ 4, 5, 16 } Do 4 and 5 when added together result in 16? NO.
Therefore, { sqrt(4), sqrt(5), sqrt(16) } does not produce a right triangle.

Your turn. Pick out the next 3 numbers and test them using the Pyth. Thm.

8 0

3 years ago

Plsplsplsplsplsplspslpslsplspslpslpslsplsplspslsp

nikdorinn [45]

Answer:

192

Step-by-step explanation:

Fist you do 4x6x4, then 6x8x2 and add em together and you get 192! :)

5 0

3 years ago

Read 2 more answers

Victoria has $200 of her birthday gift money saved at home, and the amount is modeled by the function h(x) = 200. She reads abou

svlad2 [7]

Solution :

Amount of money Victoria has = $200

The amount modelled by function = h(x) = 200

According to the function,

s(x) = (1.05)x - 1

It means that the total amount of the interest that Victoria will receive s(x) is equal to original amount of $200 which multiplied by the rate of interest (1.05) and then multiplied by the time that Victoria keeps the money in the bank (x) minus 1.

4 0

2 years ago