About a year ago a dear friend of mine passed away and was buried through my parish of Mt St. Michael's here in Spokane, WA. I had known her and her husband as well as her children for over 40 years.  Even as a child, when I remember seeing her at Mass or in Church for one reason or another to visit our Divine Lord, she ALWAYS had a Rosary in hand.  
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One of her memory cards given to those in attendance inspired me so much. It is Sr. Lucia of the Fatima message, her words to Fr. Fuentes many years ago.  I read this nearly every day now, and pray for my dear friend. There is not a moment that goes by where I do not remember saying the daily Rosary.  It was in reading the following, now that I am old enough to know and old enough to care about the power and the graces of the Rosary, that my devotion to it grew by leaps and bounds. May it help someone else to pray it with fervor as well--
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"The Most Holy Virgin, in these last times in which we live, has given a new efficacy to the recitation of the Rosary. She has given this efficacy to such an extent that there is no problem, no matter how difficult it is, whether temporal or above all spiritual, in the personal life of each one of us, of our families, of the families of the world or of the religious communities, or even of the life of peoples and nations, that cannot be solved by the Rosary. There is no problem I tell you, no matter how difficult it is, that we cannot resolve by the prayer of the Holy Rosary. With the Holy Rosary we will save ourselves. We will sanctify ourselves. We will console Our Lord and obtain the salvation of many souls."

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I have a cassette tape of a priest giving a talk from 20 years ago, in which he alludes to this quote from Fr. Fuentes.  He adds in the tape that he knew of another quote where Our Lady made it known that in appealing to her intercession by way of a 54-day Rosary novena she would not fail to grant the request. This is 27 days of supplication followed by 27 days of thanksgiving, and consisting of one 5-decade Rosary each day, Joyful, then Sorrowful, then Glorious in 3-day cycles. (That works out to 9 Rosaries of petition and 9 of thanksgiving - you pray the second set even before your request is fulfilled.)
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Is it 5 Decades or 15 Decades each day?  I heard the latter.  Thanks.

The answer is 5 Decades each day.  The following text is taken from this reliable link: 54 DAY ROSARY NOVENA

How to Say the Miraculous 54-Day Rosary Novena
The Novena consists of five decades of the Rosary each day for twenty-seven days in petition; then immediately five decades each day for an additional twenty-seven days in thanksgiving, whether or not the request has been granted.
The meditations vary from day to day. On the first day meditate on the Joyful Mysteries; on the second day the Sorrowful Mysteries; on the third day the Glorious Mysteries; on the fourth day meditate again on the Joyful Mysteries; and so on throughout the fifty-four days.