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Haven't posted for a while as things have got a little quiet (thankfully)

Anyhow, we are stuck on amths problem and urgently need either a method or a pointer to a resource

Percents:

how do you calculate a tricky percent, suchas

37 1/6 % of 45 (ie 37 and one sixth percent)

With or without a calculator, and if with, is it one with a % button? If with, it's a question of reading the manual :-)

Assuming without, it's only a question of knowing what a percentage means and doing the arithmetic:

37 1/6 % of 45 means ((37 1/6) / 100) x 45

and then it depends on whether you need it exactly or approximately. In real life, I'd say that's a wee bit more than one third of 45 or 15 and a bit more :-) The hard way, well, 37 1/6 is 223/6 isn't it, and we can cancel 5 between the 100 and the 45 and 3 between the 6 and the 45, leaving:

(223/(2x20)) x 3 = 669/40 = whatever it does equal, um, 16 and 29/40

Does that help?

Is this the answer you are looking for (ready to be plugged in a calculator )?
(37*6 +1) * 45 / 6 / 100

Or, calculating by hand,
37*6 = 222
222 + 1 = 223
So 37 1/6 % = 223/600
and 37 1/6 % of 45 = (223 * 45)/600 = (223 * 15)/200 = 3345 / 200 = 33.45 / 2 = 16.725

Darn, I typed too slow!

Better luck next time SiaSL ;-)

I am getting badly rusty -- too many years relying on calculators. My 7 yo can now out-calculate me on simple arithmetic tasks <pout>.

By fractions, 37 & 1/6 percent of 45.

Step 1: ((37 & 1/6)/100) * 45
Step 1: 6*(((37 & 1/6)/100) * 45)/6
Step 1: ((37*6+1)/100)*45/(6)
Step 1: 100*((37*6+1)/100)*45/((6)*100)
Step 1: ((37*6 + 1)*45)/(100*6)
Step 2:((222+1)*45/(600)
Step 2: (223)*45/600
Step 2: (10035)/600
Step 3: (2007*5)/(120*5)
Step 3: (2007)/(120)
Step 3: (223*3*3)/(3*4*10)
Step 3: (223*3)/(4*10)
Step 4: 16 and 29/40

Step 1: Remove divisors in numerator - 6 for 1/6 fraction and 100 for percent
Step 2: Add multipliers to denominator for the divisors removed in the numerator
Step 3: Reduce terms in both by factoring
Step 4: Restate numerator as a fraction of reduced terms