Math Is Fun Forum

haftakhan

Member

Registered: 2010-06-28

Posts: 30

Percentage Questions

1)Particular species of bird weighs about 28 grams when born.If the weight increases by 10% a day,How much will it weigh on the third day of its life ?

How can this question be solved ?

Is there any formula to help solve such percentage questions ?

2)35% of the plants in the part are broad leafed plants and the rest are gasses.What percentage of the plants are grasses ?

Is there any trick in this question ?

The answer should be 65% ?

Also i want to know how to upload an image ?As i tried and selected a jpeg file but there was no option to attach it or no upload button avaiable

Bob

Administrator

Registered: 2010-06-20

Posts: 10,649

Re: Percentage Questions

A 10% increase is the same as multiplying by 1.1 so just do 28 x 1.1 x 1.1 x 1.1=
The formula would be multiplier = 1 + percentage/100     eg. Increase by  25% becomes 1 + 25/100 = 1.25

and decrease by 20% becomes 1 - 20/100 = 0.8

If you've got two sorts of plants and 35% are one type then the rest must be 100 - 35 = 65%.  No trick.

If you do a 'quick post' then all you can do is type some text.

If you click on 'Post reply' you get more options.  Under the text space you must select how many images you want to upload and then you browse your computer to find them on your hard disc.

I often edit my posts after I've sent them because I've spotted a spelling mistake or want to add to an explanation.  There's a button for this too.  But I've never managed to edit a picture once I've sent it.

Last edited by Bob (2010-08-17 01:37:52)

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Sometimes I deliberately make mistakes, just to test you!  …………….Bob