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In a flowerbed, there are only marigolds and roses.

The ratio of ladybugs on the marigolds to ladybugs on the roses was 2:3.

6 ladybugs moved from the roses to the marigolds, and the ratio became 7:8.

Work out how many ladybugs were on the marigolds to begin with.

User Reden
by
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1 Answer

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Answer:

36 ladybugs on the marigolds.

Explanation:

Let's denote the initial number of ladybugs on the marigolds as

2

2x (since the ratio is 2:3) and on the roses as

3

3x.

After 6 ladybugs moved from the roses to the marigolds, the new ratio becomes 7:8. So, the new number of ladybugs on the marigolds is

2

+

6

2x+6 and on the roses is

3

6

3x−6.

The new ratio is given as:

2

+

6

3

6

=

7

8

3x−6

2x+6

=

8

7

Now, cross-multiply to solve for

x:

8

(

2

+

6

)

=

7

(

3

6

)

8(2x+6)=7(3x−6)

Expand and solve for

x:

16

+

48

=

21

42

16x+48=21x−42

48

+

42

=

21

16

48+42=21x−16x

90

=

5

90=5x

=

18

x=18

Now that we have the value of

x, we can find the initial number of ladybugs on the marigolds:

2

=

2

×

18

=

36

2x=2×18=36

So, there were initially 36 ladybugs on the marigolds.

User Wouter Overmeire
by
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