I stand corrected.

]]>I did it like this:

D = original number of production days (10).

Chairs: final 16 is > original 8, resulting in increased production days of:

(a) D x 16/8.

Carpenters: final 10 is > original 2.6, resulting in reduced production days of (a) x 2.6/10.

The resulting sum:

Sorry, I didn't see the 2 previous posts until now...but I'll post mine anyway.

]]>If you have more carpenters it will take less days so this is inverse proportion.

If you have to make more chairs this will take more days so this is direct proportion.

I'll use these symbols: original carpenters = a; original chairs = b; original days = c

new carpenters = d; new chairs = e.

Change the number of carpenters from a to d. Inverse => multiply by a/d

so new days = c x a/d

Change the number of chairs from b to e. direct => multiply by e/b

so new days = c x a/d x e/b

In your problem a = 2.6; b = 8; c = 10; d = 10; e = 16

Therefore the new number of days = 10 x 2.6/10 x x 16/8 = 2.6 x 2 = 5.2

If you want to test this, try varying the values of a to e and satisfy yourself that the formula works.

Bob

]]>Always reckon number of men/days/hours/number of items; that is how I did it.

]]>This is an example of two proprtion questions 'welded' together. I find it best to just change one thing at a time.

2.6 carpenters can make 8 chairs in 10 days

If we want to still take 10 days we will have to double the number of carpenters.

So ( 2.6 x 2 ) carpenters can make 16 chairs in 10 days

But we have more carpenters to do this. The ratio of old number to new number is 2.6 x 2 : 10. More carpenters means less days so this is an inverse proportion. So the number of days will reduce in the ratio 10 : 2.6 x 2

Thus

]]>I'd appreciate it if you would help me with this question. ?

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