|PR| = |PQ| + |QR|; |PQ| = |QR| conclusion |PR| = 2|PQ|
|PQ| = 3y; |PR| = 42; |QR|=?
subtitute
42 = 2(3y)
6y = 42 |divide both sides by 6
y = 7
|QR| = 3(7) = 21
Answer:
Step-by-step explanation:
Let the total amount be x
Then Ali got 1/8x With 7/8x left
Juma got 7/40x with 7/10x left
Musa, Khalid and Mustafa got 7/30x each
since 
7x=18000
Answer:
29.7 is the standard deviation :)
Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
_____
You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
