 In one household there live four sisters of different heights. Their average height is 74 inches, and the difference in height among the first three women is two inches. The difference between the third and the fourth women is six inches.
Can you tell how tall is each sister?

 Consider the height of 4 sisters as a, b, c, d respectively. Let x be equal to a. Therefore, Height of 1st sister= x Height of 2nd sister= x+2 Height of 3rd sister= (x+2)+2 = x+4 Height of 4th sister= ((x+4)+6= x+10 There average height= 74 ∴ (a+b+c+d)/4=74 a+b+c+d=74*4= 296 ∴x+(x+2)+(x+4)+(x+10)=296   4x + 16 = 296   4x = 280   x  = 70 So, Height of 1st sister is 70 inch Height of 2nd sister is 72 inch Height of 3rd sister is 74 inch Height of 4th sister is 80 inch

Fifty minutes ago it was four times as many minutes past three o’clock. How many minutes is it to six o’clock?

 Consider that x minutes are left to six o’clock. The time difference between 3 o’clock to 6 o’clock is 3 hours i.e. 180 minutes. Therefore, 4 times x is  equal to the minutes left for 6 The current time is 6 o’clock -x minutes or 180-x Time 50 minutes ago, left to 6 pm is 180-x-50=(130-x) 130-x=4x x=26 minutes

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