Respuesta :

1) B=Bikers H=Hikers

H=B+178 (178 MORE HIKERS THAN BIKERS)

B+H=676 (TOTAL EQUATION)

COMBINE EQUATIONS (Plug in H from first equation into second one)
  B + B +178 = 676
SOLVE FOR B
2B=498
B=249 Total Bikers

Now for Hikers go back to the first equation we made

H= B+178.... Plug in B =249 and get

H=427

2) Children =C AND Adult =A

C+A=764  .............. C=764-A

2C+5A=2992

COMBINE EQUATIONS

2(764-A)+5A=2992

You can solve for A.
A=488

Now c GO BACK TO FIRST EQAUTION
C+A=764 and solve for C.

C=276