Let the required length be L m.
More men, More length (Direct proportion)
Less days, Less length (Direct proportion)
Men 20 : 70
Days 6 : 3
∴ (20 x 6 x L) = (70 x 3 x 56)

Correct Option: B

Let the required length be L m.
More men, More length (Direct proportion)
Less days, Less length (Direct proportion)
Men 20 : 70
Days 6 : 3
∴ (20 x 6 x L) = (70 x 3 x 56)
∴ L = (70 x 3 x 56) / (20 x 6) = 98 m

Let the required number of days be N.
Remaining work = 1 - 5/8 = 3/8
Less work, Less days (Direct proportion)
5/8 : 3/8 : : 20 : N

Correct Option: D

Let the required number of days be N.
Remaining work = 1 - 5/8 = 3/8
Less work, Less days (Direct proportion)
5/8 : 3/8 : : 20 : N
⇒ N = (3/8) x 20 x 8/5
∴ N = 12 days

∵ In 2/3h, 1 article is made.
∴ In 1h, 3/2 article are made.

Correct Option: A

∵ In 2/3h, 1 article is made.
∴ In 1h, 3/2 article are made.
∴ In 7¹/₂ = 15/2h, 3/2 x 15/2 = 45/4 article are made.
∴ Required articles = 45/4 = 11²/₄

Let the required number of days be N.
Let men, More days (indirect proportion)
8 : 12 : : 24 : N

Correct Option: B

Let the required number of days be N.
Let men, More days (indirect proportion)
8 : 12 : : 24 : N
∴ N = (12 x 24)/8 = 36 days

∵ Price of m articles = ₹ n
∴ Price of 1 article = ₹ n/m

Correct Option: A

∵ Price of m articles = ₹ n
∴ Price of 1 article = ₹ n/m
∴ Price of 5 articles = ₹ 5n/m