The ratio of the number of rambutan trees to the number of mango trees

was 5:3. After 12 more rambutan trees were planted, the new ratio became 11:6

How many mango trees were there?

Guest Feb 15, 2022

#1**+1 **

R==Rambutan trees, M==Mango trees

R / M ==5 / 3.....................(1)

[R + 12] / M ==11 / 6..........(2)

From (1) above, we have:

M ==3R / 5

Substitute for M in ( 2) above:

[R + 12] / [3R / 5] ==11 / 6

Solve for R:

(5 (R + 12))/(3 R) = 11/6

Cross multiply:

30 (R + 12) = 33 R

Expand out terms of the left hand side:

30 R + 360 = 33 R

Subtract 33 R + 360 from both sides:

-3 R = -360

Divide both sides by -3:

**R = 120 - Number of Rambutan trees**

Sub into (1) above:

120 / M ==5 / 3

Cross multiply

5M ==360

M ==360 / 5

**M ==72 - Number of Mango trees**

Guest Feb 15, 2022