Advertisements
Advertisements
प्रश्न
If (x – 9) : (3x + 6) is the duplicate ratio of 4 : 9, find the value of x.
Advertisements
उत्तर
`(x - 9)/(3x + 6) = (4/9)^2`
⇒ `(x - 6)/(3x + 6) = (16)/(81)`
⇒ 81x – 729 = 48x + 96
⇒ 81x – 48x = 96 + 729
⇒ 33x = 825
⇒ x = `(825)/(33)`
= 25.
APPEARS IN
संबंधित प्रश्न
Find the compound ratio of :
3 : 5 and 8 : 15
If m : n = 3 : 8, find the value of (3m+2n) : (5m+n)
Find the sub-duplicate ratio of the following :
`1/16 : 1/36`
Find the sub-triplicate ratio of the following :
125a3 : 343b6
Find the ratio of the price of a pencil to that of a ball pen if pencils cost Rs 96 per score and ball pens cost Rs 50.40 per dozen.
Out of 50 students in a class, 30 are boys. Find the ratio of number of boys to the total number of students
The ratio of 1 hour to one day is 1 : 1.
Samira sells newspapers at Janpath crossing daily. On a particular day, she had 312 newspapers out of which 216 are in English and remaining in Hindi. Find the ratio of the number of English newspapers to the number of Hindi newspapers.
In the following figure, what is the ratio of the areas of
- shaded portion I to shaded portion II?

- shaded portion II to shaded portion III?
- shaded portions I and II taken together and shaded portion III?
A doctor reports blood pressure in millimeters of mercury (mm Hg) as a ratio of systolic blood pressure to diastolic blood pressure (such as 140 over 80). Systolic pressure is measured when the heart beats, and diastolic pressure is measured when it rests. Refer to the table of blood pressure ranges for adults.
| Blood Pressure Ranges | |||
| Normal | Prehypertension | Hypertension (Very High) |
|
| Systolic | Under 120 mm Hg | 120-139 mm Hg | 140 mm Hg and above |
| Diastolic | Under 80 mm Hg | 80-89 mm Hg | 90 mm Hg and above |
Manohar is a healthy 37 years old man whose blood pressure is in the normal category.
- Calculate an approximate ratio of systolic to diastolic blood pressures in the normal range.
- If Manohar’s systolic blood pressure is 102 mm Hg, use the ratio from part (a) to predict his diastolic blood pressure.
- Calculate the ratio of average systolic to average diastolic blood pressure in the prehypertension category.
