4(30) + 30x = 90x
Solve for x.
a coast guar ship left a port at 30 mph. four hours later a helicopter was dispatched at 90 mph to intercept the ship. how long will it take the helicopter to catch the ship?
2 answers
Finding by ratio as follow
ship 30 mph
total distant in 4 hours is 30*4=120 mph
helicop 90 mph
so ratio
MPH DISTANT MPH DISTANT
120 4 90 X
120*X = 360
X = 360/120
X = 3
SO X = 4-3
X = 1 HOUR THE HALI WILL CATCH THE SHIP
YOURS EQUATION 4(30) + 30x = 90x IS NOT CORRECT COZ THE SOLUTION LL BE 120=90X-30X
120=60X
60X=120
X=120/60
X=2 MEANS THAT THE THE SHIP IS HALF SPEED OF HALI WHICH IS NOT CORRECT.
ship 30 mph
total distant in 4 hours is 30*4=120 mph
helicop 90 mph
so ratio
MPH DISTANT MPH DISTANT
120 4 90 X
120*X = 360
X = 360/120
X = 3
SO X = 4-3
X = 1 HOUR THE HALI WILL CATCH THE SHIP
YOURS EQUATION 4(30) + 30x = 90x IS NOT CORRECT COZ THE SOLUTION LL BE 120=90X-30X
120=60X
60X=120
X=120/60
X=2 MEANS THAT THE THE SHIP IS HALF SPEED OF HALI WHICH IS NOT CORRECT.