How to do convert LSD to decimal?

LSD to decimal

Decimeter c1968 - Old to new money converter
Decimeter c1968 - Old to new money converter

To convert an amount in pounds shillings and pence to decimal, follow the steps below.

1. Convert the shillings to old pence. Remember that there are 12 old pennies in a shilling.

2. Add the old pence to the total from 1. above.

3. Divide the total old pence quantity by 2.4 rounding up or down as needed.

4. Leave the quantity in pounds as it is and add the new pence.

eg convert £5 17s 6d to decimal:

1. Convert 17 shillings from £5 17s 6d to old pence. 17 shillings is 17 x 12d = 204d .

2. Add the 6d from £5 17s 6d to make 210d .

3. Divide 210 by 2.4 to get 87.5p and round up to 88p as we don't have the ½p anymore.

4. Add to the amount in pounds from £5 17s 6d to get £5.88 .

Decimal to LSD

To go the other way reverse the process.

1. The quantity in pounds does not change

2. Convert the amount in new pence to old pence by multiplying by 2.4

3. Divide the amount in old pence by 12 to get the amount in shillings.

4. The remainder will be the amount in old pence.

eg convert 5.88 to old money:

1. Save the £5 from £5.88. This will not change

2. Convert the 88p to old pence by multiplying by 2.4. We get 211d rounding down.

3. Find the amount in shillings by dividing by 12 and ignoring the remainder. 211/12 = 17 so 17s

4. The remainder is 211 - (17 x 12) = 7d

The total is £5 17s 7d. You notice we do not get the same amount. This is because we ignored the ½p in the LSD to decimal calculation.

Quick method

For a quick way to convert from decimal to £sd, multiply the decimal amount by 2 and put a shilling '/' before the last digit.

eg to convert 78p to £sd:

78 x 2 = 156

Convert to £sd by inserting the stroke, you get 15/6 or 15 shillings and 6 pence. It is actually 77½p, but is close enough.

To go the other way reverse the process.

15/6 -> 156p

Divide by 2 = 78p

Other quick conversions:

Sixpence is 2p or two and a half new pence

One shilling is 5p.

One guinea is £1.05

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