Answer:
a = 1/42, b = 1/7, c = 1/3 and d = 1/2
Step-by-step explanation:
a = bcd (1)
a + b = cd (2)
a + b + c = d (3)
a + b + c + d = 1 (4)
Substituting equation (3) into equation (4), we have
a + b + c = d (3)
a + b + c + d = 1 (4)
(a + b + c) + d = 1 (4)
d + d = 1 (5)
2d = 1
dividing through by 2, we have
d = 1/2
Taking equation (2) and equation (3), we have
a + b = cd (2)
a + b + c = d (3)
substituting equation (2) into equation (3), we have
a + b = cd (2)
(a + b) + c = d (3)
cd + c = d
Factorizing, we have
c(d + 1) = d
dividing through by d + 1, we have
c = d/(d + 1)
substituting d = 1/2 into the equation, we have
c = d/(d + 1)
c = 1/2 ÷ (1/2 + 1)
c = 1/2 ÷ 3/2
c = 1/2 × 2/3
c = 1/3
Taking equations (1) and (2), we have
a = bcd (1)
a + b = cd (2)
Substituting equation (1) into (2), we have
a = bcd (1)
a + b = cd (2)
bcd + b = cd (2)
Factorizing, we have
b(cd + 1) = cd
dividing through by (cd + 1), we have
b = cd/(cd + 1)
substituting the values of c and d into the equation,, we have
b = cd/(cd + 1)
b = 1/3 × 1/2/(1/3 × 1/2 + 1)
b = 1/6/(1/6 + 1)
b = 1/6 ÷ 7/6
b = 1/6 × 6/7
b = 1/7
Since a = bcd, substituting the values of b,c and d into the equation, we have
a = bcd
a = 1/7 × 1/3 × 1/2
a = 1/42
So, a = 1/42, b = 1/7, c = 1/3 and d = 1/2
