The discount is $7, and Mrs.Hill only has to pay $28.
Responder:
Número total de bolas = 245/23
Explicación paso a paso:
Dado que:
Bolas blancas = 1/5
Bolas negras = 1/7
Bolas rojas = 7
Sea el número total de bolas = x
Bolas blancas = 1 / 5x
Bolas negras = 1 / 7x
Por tanto, total;
(x / 5 + x / 7 + 7) = x
((7x + 5x) / 35) +7 = x
(12x / 35) + 7 = x
7 = x - 12x / 35
7 = (35x - 12x) / 35
7 = 23 veces / 35
245 = 23x
x = 245/23
The smallest possible value of z is the denominator of the reduced fraction x/y. We note the prime factors of the members of set y are
... 2², 7, 2³, 3²
so if there are any even members of set x, the fraction can be reduced to something divided by 2. The number 6 in set x is even, so we have
... 6z/4 = 6·2/4 = 3 (an integer) when z=2
The lowest possible value of z is ...
... B) 2
Answer:
(a) is 15
(b) is 30
75 divide by 15 times 90 divide by 15 is 30
