1 - 2/7 = 5/7
5/7 of the oranges are left.

We can see it as :
5 units out of 7 units of oranges are left.


But we see that the ratio of oranges to kiwis left is 2 : 1

What you want to do is to make the number of units the same.

Lowest common multiple of 2 and 5 is 10

Change 5/7 to 10/14

Change 2 : 1 to 10 : 5


So we can now say :

10 units of oranges and 5 units of kiwis are left.
There were 14 units of oranges at first.

(Do note that the unit size here is not the same as the one we wrote about at the start. It is actually half the size only)

358 = 14 units (all the oranges) + 5 units kiwis left) + 35 (kiwis sold)


358 - 35 = 19 units
323 = 19 units
1 unit = 323 ÷ 19 = 17

Total number of oranges left

= 10 units + 5 units
= 15 units

= 15 × 17
= 255

Thank you so much. This method is easier to understand.

This method is p5/p6 method. I would strongly discourage algebra method at your level

Yes, algebra still confuses me a little. Thank you once again