F.1 Maths !請入!!THZ! step+ans!

1.Let y be the larger number.
2y + 1/4(y-2) =49
2y + 1/4y - 1/2=49
9/4y=99/2
y=22
Therefore, the smaller even number is 20 and the larger one is 22.

2.Let y be A's age and z be his son's age.
y+z=51-------1
y-3=8(z-3)---2
From 1, y=51-z----3
Substitude 3 into 2,
51-z-3=8(z-3)
48-z=8z-24
72=9z
z=8
Therefore. his son is at the age of 8 now.

1)Let the smaller number be x,the larger number be (x+2).

2(x+2) + 1/4x = 49

2x+ 4 + 1/4x = 49

2/1/4x = 49 - 4

2/1/4x = 45

x = 20

The two consecutive are 20 and 21.

2)Let his son is x years old now.

8x + x = 51 -3 - 3

9x = 45

x = 5

His son is 5 years old now.

1) Let the smaller number be y, the larger number be (y+2)

2 times the larger one plus 1/4 of the smaller one equals 49, to express it in the form of equation:
2 (y+2) + y (1/4) = 49
9y = 180
y = 20

thus y + 2 = 22

therefore, the 2 consecutive even numbers are 20, 22


2) Let his son's age now be y
total age of A and his son is 51, therefore, A's age now is (51-y)

three years ago, A was 8 times as old as his son
(51-y) - 3 = 8 (y -3)
9y = 72
y = 8

therefore, his son is 8 years old now.