SOLUTION: the ratio of boys is to girls is 7:9 . if the enrolment is of the school is 786,how many boys are there?

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Question 1034519: the ratio of boys is to girls is 7:9 . if the enrolment is of the school is 786,how many boys are there?
Found 2 solutions by ikleyn, josmiceli:
Answer by ikleyn(52832) About Me  (Show Source):
You can put this solution on YOUR website!
.
the ratio of boys is to girls is 7:9 . if the enrolment is of the school is 786,how many boys are there?
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Wrong data.


Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +b+ = number of boys
Let +g+ = number of girls
-------------------------
(1) +b%2Fg+=+7%2F9+
(2) +b+%2B+g+=+786+
--------------------
Multiply both sides of (1) by +9g+
(1) +9b+=+7g+
Divide both sides by +7+
(1) +g+=+%289%2F7%29%2Ab+
Substitute this result into (2)
(2) +b+%2B+%289%2F7%29%2Ab+=+786+
Multiply both sides by +7+
(2) +7b+%2B+9b+=+5502+
(2) +16b+=+5502+
(2) +b+=+343.875+
Rounded off, there are 344 boys
and
(1) +g+=+%289%2F7%29%2Ab+
(1) +g+=+%28+9%2F7+%29%2A343.875+
(1) +g+=+3094.875%2F7+
(1) +g+=+442.125+
-----------------------
check:
(2) +b+%2B+g+=+786+
(2) +343.875+%2B+442.125+=+786+
(2) +786+=+786+
and
(1) +b%2Fg+=+7%2F9+
(1) +343.875%2F442.125+=+7%2F9+
(1) +.7777+=+.7777+
OK
Since the number of boys and girls do not
come out whole numbers, I suspect the given
data is wrong somehow -either copied wrong
or just wrong as it is given.