Step-by-step explanation:
Let the numbers are 4x and 7x. According to the question if each number is increased by 20, the ratio becomes 7 : 9.
Then,
( 4x + 20 ) : ( 7x + 20 ) = 7 : 9
9( 4x + 20 ) = 7( 7x + 20 )
9( 4x ) + 9( 20 ) = 7( 7x ) + 7( 20 )
9( 20 ) - 7( 20 ) = 7( 7x ) - 9( 4x )
2( 20 ) = 49x - 36x
40 = 13 x
40 / 13 = x
Therefore, number are :–
4 x = 4( 40 / 13 ) = 160 / 13
7 x = 7( 40 / 13 ) = 280 / 13
Answer: he should invest $16129 today.
Step-by-step explanation:
Let $P represent the initial amount that should be invested today. It means that principal,
P = $P
It would be compounded annually. This means that it would be compounded once in a year. So
n = 1
The rate at which the principal would be compounded is 7.6%. So
r = 7.6/100 = 0.076
The duration of the investment would be 6 years. So
t = 6
The formula for compound interest is
A = P(1+r/n)^nt
A = total amount in the account at the end of t years.
A = 25000
Therefore
25000 = P(1+0.076/1)^1×6
25000 = P(1.076)^6
25000 = 1.55P
P = 25000/1.55
P = $16129
Answer:
(x-6)(x-4) = 0
Step-by-step explanation:
Subtract 5 from both sides to make the equation equal to 0. You will get the equation x2-10x+24=0. Now think of two numbers that multiply to get 24 but add to get -10. These numbers are -6 and -4. The factors of x2 are x and x which multiply to get x2. Now put two linear factors into parathesis to get (x-6)(x-4) = 0.
Answer:
18.84 cm
Step-by-step explanation:
P = 2 × pi × r
= 2 × 3.14 × 3cm
= 6cm × 3.14
= 18.84 cm
