Question 370037
let it walk x cm
let it crawl y cm
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x/4  + y/3 = 110
3x+4y /12= 110
3x+4y = 1320.....................1
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x/3 + y/4 = 100
4x+3y / 12 = 100
4x+3y= 1200......................2
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multiply equation 1 by -4 & equation 2 by 3
-12x-16y= -5280
12x+9y = 3600
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add the two equations
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-7 y = -5280+3600
-7y = -1680
y = -1680/-7
y = 240 cm  crawl
plug value of y in equation 1
3x+4y=12*110
3x+960=1320
3x=1320-960
3x=360
x = 120 cm walking 


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