2Decrease R420 in the ratio 4:7

Mathematics

1 answer:

Oxana [17]3 years ago

4 0

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

You might be interested in

In Kayllie'srecipe for lemonade, the ratio of lemons to water is 7 to 4. People are complaining that the lemonade is too weak. W

katrin [286]

Answer:

B.) 10 to 5 and D.) 8 to 4.

Step-by-step explanation:

Since we are trying to make the lemon taste stronger, there would need to be more lemons than water. The ratio would need to have a larger difference than 7:4. The difference is 3.

Choice A has a difference of 2. Two is less than 3 so this would taste more watery than lemony. Choice C has a difference of 3. Because we want a stronger lemon taste, this won't work. It would taste the same.

Choice B has a difference of 5. This is greater than 3 so the lemon taste will be stronger. Choice D has a difference of 4, this is also greater than 3 and will also make the taste of lemon stronger.

Hope this helps,

♥A.W.E.S.W.A.N.♥

5 0

3 years ago

The function L = 0.8T^2 models the relationship between L, the length in feet of a pendulum, and T, the period in seconds of the

Semmy [17]

The correct option is "d".
Given that L = 0.8T²
length of pendulum = 30ft

L= 0.8T²
30 = 0.8T²
T² = 30 / 0.8
T² = 37.5
T = √37.5 = 6.1 seconds
So, 6.1 is the closest to the period in seconds for a pendulum that is 30 ft long.

7 0

3 years ago

Kate buys 10 tickets to a show. She also pays a $5 Parking fee. she spent $35 to see the show. what is the equation to this prob

zepelin [54]

Answer:

(35 - 5)/10 = 3

Step-by-step explanation:

She paid 35 alltogether and 5$ was for parking, so we can subtract that. Then 30/10 is equal to 3 so she spent 3 dollars for each ticket!

5 0

3 years ago

-2x + 9x What is the answer

Blababa [14]