Anonymous
Anonymous asked in Science & MathematicsMathematics · 1 decade ago

math questions. please help!?

1. at noon, a train leaves bridgton heading east at 90 mi/hr to cogsville, 450 miles away. at 12:15pm a train leavs cogsville heading west to brigdton at 100 mi.hr. at what time will they pass each other?

2. a jar contains 40 coins consisting of dimes and quarters and having a total value of $4.90. how many of each kind of coin are there?

3. a man invested $6000, part of it at 5% simple interest and the rest at 7% simple interest. if his annual interest is $372, how much did he invest at each rate?

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  • Anonymous
    1 decade ago
    Favorite Answer

    I will get back with you A.S.A.P. Cheers!

  • 1 decade ago

    1. After 15 minutes, the first train has travelled 22.5 miles. The trains are now 427.5 miles apart. Since they approach each other at a combined speed of 190 m/h, they will pass in 2 ¼ hours, at 2:30 pm.

    2. d + q = 40

    10d + 25q = 490 Solve simultaneous equations.

    10d + 10q = 400

    15q = 90

    q = 6 --> d = 34

    3. S1 + S2 = 6000 (S for "stash." Why not.)

    S1*.07 + S2*.05 = 372 Simul eqs again.

    S1*.05 + S2*.05 = 300

    S1*.02 = 72

    S1 = $3600 S2=$2400

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