Maths question

BUDFORCE

BUDFORCE

BUDFORCE

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I'm terrible at maths.

I have two figures.

11,400

12,500

To achieve what I need to do, I can only use 40% of the second figure as a total of both figures combined.

Through lots of trail and error and an embarrassingly large amount of time, I managed to work this out as 7,600.

7,600 + 11,400 = 19,000 or 40% of 19,000 = 7,600.

Is there a quick way to work this out?
 
Erm... 11,400/60*100-11,400.

Gives the 7,600 answer by assuming that 11,400 is 60% of the whole and then calculating the 100% figure and subtracting the original 60% figure.

Probably an easier way to do it, too :D
 
BUDFORCE said:
I'm terrible at maths.

I have two figures.

11,400

12,500

To achieve what I need to do, I can only use 40% of the second figure as a total of both figures combined.

Through lots of trail and error and an embarrassingly large amount of time, I managed to work this out as 7,600.

7,600 + 11,400 = 19,000 or 40% of 19,000 = 7,600.

Is there a quick way to work this out?
Click to expand...
What? Where does 12,500 fit into this?
 
kaiowas said:
I’m sure the maths is trivial. What I can’t work out is what you are actually trying to do. Your first post makes no sense. What does “I can only use 40% of the second figure as a total of both figures combined.” even mean?
Click to expand...

Ok you asked......

I am looking at a semi-commercial mortgage application, so the property is freehold with commercial unit at the ground floor, residential above.

We have this stupid criteria that we can only factor in a maximum of 40% of the commercial rental income for working out BTL affordability.

The valuer came back and said the residential gets £11,400 p/a and the commercial gets £12,500 p/a.

Obviously on those figures the commercial element way exceeds 40% of the total and its outside of criteria. So you try to make it fit, we were trying to work out what was the max amount of the total rent we could use, whilst not exceeding 40% of the commercial element.
 
You need to post the wording, that is still confusing.

To me, what you've written seems to imply that the lender is limiting the income on the commercial property to 40% of what you could receive on that part of it.

Most probably because commercial properties are hard to let out and are likely to see periods of being unoccupied, which the lender believes will be about 60% of the time.

Residential lets are in short supply so the lender is probably happy that you use 100% of the potential income because its unlikely to be unoccupied for any significant period.
 
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BUDFORCE said:
Ok you asked......

I am looking at a semi-commercial mortgage application, so the property is freehold with commercial unit at the ground floor, residential above.

We have this stupid criteria that we can only factor in a maximum of 40% of the commercial rental income for working out BTL affordability.

The valuer came back and said the residential gets £11,400 p/a and the commercial gets £12,500 p/a.

Obviously on those figures the commercial element way exceeds 40% of the total and its outside of criteria. So you try to make it fit, we were trying to work out what was the max amount of the total rent we could use, whilst not exceeding 40% of the commercial element.
Click to expand...

40% of the commercial element is 0.4 * 12,500 = £5000.

So is it not just £5000 + £11,400 = £16,400 total?

Or are you saying:
- Given you have total rent X, no more than 40% of X can be made up of commercial rent? In which case 60% of X will be residential rent.
- So 0.6X = 11,400
- So X = 11,400/0.6 = 19,000
- 19,000 - 11,400 = 7,600 which is the max amount of commercial rent you can include. (But just remember this would mean 7600/12500 = 60.8% of the commercial rental)

Which one it is depends on the exact wording of the rules.
 
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I think our OP means that the commercial element can only account for a maximum of 40% of the total amount. Since it's clearly substantially more than that, this can easily be calculated as a total of 5/3rds of £11400 which is £19000 or £11400 residential + £7600 commercial.

However, I think our OP should carefully check the wording because I think they've misunderstood and the inclusion of 40% of the value of the commercial income (in this case, £5000) is the more likely rule.
 
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BUDFORCE said:
I'm terrible at maths.

I have two figures.

11,400

12,500

To achieve what I need to do, I can only use 40% of the second figure as a total of both figures combined.

Through lots of trail and error and an embarrassingly large amount of time, I managed to work this out as 7,600.

7,600 + 11,400 = 19,000 or 40% of 19,000 = 7,600.

Is there a quick way to work this out?
Click to expand...

Work what out? Try asking the question again. Where did you get 19000 from?
 
x = residential element
y = commercial element

The maximum of the commercial element (y) is 40% of the sum of x and y, i.e.:

y <= 0.4(x + y)

So, if y > 0.4(x + y), we can use the formula to maximise y:

y = 0.4(x + y)

Rearranging:

y = 0.4x + 0.4y
0.6y = 0.4x
y = (0.4/0.6) x
y = 2/3 x

Assuming x is fixed

x = 11400
y = 2/3x

y = 7600

x + y = 19000

So in general:

y = 2/3 x for all cases where y > 0.4(x + y)
 
AndyT said:
x = residential element
y = commercial element

The maximum of the commercial element (y) is 40% of the sum of x and y, i.e.:

y <= 0.4(x + y)

So, if y > 0.4(x + y), we can use the formula to maximise y:

y = 0.4(x + y)

Rearranging:

y = 0.4x + 0.4y
0.6y = 0.4x
y = (0.4/0.6) x
y = 2/3 x

Assuming x is fixed

x = 11400
y = 2/3x

y = 7600

x + y = 19000

So in general:

y = 2/3 x for all cases where y > 0.4(x + y)
Click to expand...

How to overcomplicate a trivial solution ^ :p

Minato said:
Or are you saying:
- Given you have total rent X, no more than 40% of X can be made up of commercial rent? In which case 60% of X will be residential rent.
- So 0.6X = 11,400
- So X = 11,400/0.6 = 19,000
- 19,000 - 11,400 = 7,600 which is the max amount of commercial rent you can include. (But just remember this would mean 7600/12500 = 60.8% of the commercial rental)
Click to expand...
 
honestly I don't understand the question... even after reading other peoples comments... (serveal times!!)

commercial = 12,500
residential = 11,400

You are only allowed to get 40% of the commercial (12,500)... 12,500 * 0.4 = 5,000

5,000
+ 11,400
= 16,400

I'll be amazed if I get this right, thank the lord you don't write exam questions.. lol
 
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