# Ratio question

#### Enos

I've been trying to get the ratio of the french minute of 100 seconds and the standard minute 60 seconds. The textbook gives me answer of 0.084 and I can mess with these numbers and eventually change 60 to 100 or vise versa. I tried google but they only do 1:4 type of ratios and the textbook wants "0.084" kind of answers. Can someone help and describe how to find ratios?

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#### HallsofIvy

Homework Helper
First, I'm amazed to hear that the "French" minute has 100 seconds! When did that happen?

Secondly, assuming that "French" seconds are as long as our seconds, then the ratio of the length of a "French" minute to a "regular" minute is 100/60= 1.666....
The ratio of a "regular" minute to a "French" minute is 60/100= 0.60. I don't know where one would get 0.084.

#### brewnog

Gold Member
A ratio is simply the amount of something related to the amount of something else.

If you have 3 apples, and 2 bananas, the ratio of apples to bananas is 3:2, which you can express as 1.5. (3/2=1.5). In other words, for every 1.5 apples, there is 1 banana.

Now then, for your question, you need to know how big a "French" minute is compared to a standard minute. In the French revolutionary system, each day was split up into 10 hours, with each hour containing 100 minutes. This compared with standard time, where there are 24 hours in a day, and 60 minutes in each hour. Both days last for the same length of time!

So. Work out how many minutes there are in the "French" day, and work out how many minutes there are in the standard day. Then you can express them as either a ratio (a:b), a fraction (a/b) or a decimal.

Sorry if you feel that I've patronised you!

#### brewnog

Gold Member
HallsofIvy said:
First, I'm amazed to hear that the "French" minute has 100 seconds! When did that happen?

Secondly, assuming that "French" seconds are as long as our seconds, then the ratio of the length of a "French" minute to a "regular" minute is 100/60= 1.666....
The ratio of a "regular" minute to a "French" minute is 60/100= 0.60. I don't know where one would get 0.084.
No, the ratio of a "French" minute to a standard minute would be 1000/1440 (0.69). Still not sure where 0.084 is coming from though, but I'm hungover so have an excuse for error.

French Revolutionary Time

Don't worry, it was abandoned in 1806! #### Enos

Sorry about that, I posted the question from what I remember from the textbook and looked at the wrong answers in the text book which totally threw me off track and made me question my methods.

#### brewnog

Gold Member
Apology accepted! #### Enos

I think I still might be doing something wrong. Let me write the full question.

For about 10 years after the French Revolution, the French government attempted to base measures of time on multiples of ten: One week consisted of 10 days, one day consisted of 10 hours, one hour consisted of 100 minutes, and one minute consisted of 100 seconds. Waht are the ratios of (a) the French decimal week to the standard week and (b) the French decimal second to the standard second.

The answers the textbook give are (a) 1.43; (b) 0.864

#### brewnog

Gold Member

The key to both parts is realising that both the "French" and standard days are the same length, in real terms, because the day is based on a rotation of Earth about its axis. All other units of time are (for the purposes of the question) arbitrary.

So, for the first part, work out how many days there are in a "French" week, and how many days there are in a Standard week. This is easy, you're given it in the question. Then just express them as a ratio, fraction, or decimal as you choose.

For the second part, work out how many "French" seconds there are in a "French" day, and how many Standard seconds there are in a Standard day. Then, express them as a ratio, fraction, or decimal as you choose.

Heh, Thanks.

#### Dr.nour

hi my name is Nour
your question is small Question deceptive
where when the textbook say "french minute of 100" it mean that the french minute is equal to the standard minute .
the think that the textbook want the ratio between 1 minute and 40 seconds to 60 seconds

#### Dr.nour

the ratio might be 1.40:60 = 0.023 or 100:60 =1.66666 or 5:3 i try to make another answer .

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