some calculation

1.Question: 
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Fabric Length 100yds width 58 inch (Open) GSM 230, what is fabric weight?

Ans:Fabric weight in Kg = Length (Meter) X Width (Meter) X GSM in Kg

W (Kg)
= L x W x GSM= (100 Yds X 36 X 2.54)/100 X (58 X 2.54)/100 X 230/1000
= 91.44 x 1.4732 x .230
= 30.99 kg

2.Question:
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Fabric weight 50 kg, Fabric width 40 inch (tube) GSM 180. What is fabric length in meter?

Ans: Fabric weight in Kg = Length (Meter) X Width (Meter) X GSM in Kg

W (Kg) = L x W x GSM

50 = L x (40x 2.54x 2)/ 100 X 180/1000

L
= 136.70 meter 
= 136.70 x 1.0937 yds [ 1 meter = 1.0937 yds]
= 149.50 yds

3.Question: 
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Fabric price 2.25 USD/ yds, Width 45 inch open, GSM 200,Consumption 3.20 kg / doz, what is the garment fabric cost for per doz garments?

Ans: Fabric weight in Kg = Length (Meter) X Width (Meter) X GSM in Kg

W (Kg) = L x W x GSM

= L (M) X (45X2.54)/100 X 200/1000

L (M)
= (3.20 X100X 1000) / (45X 2.54 X 200)
= 13.99 (M)
= 13.99 X 1.0937 yds
= 15.30 yds

Fabric cost (Per doz gmt)
= Length X Unit price/ yds
= 13.99 (M)
= 15.30 x 2.25
= 34.56 USD / Doz