Answer:
70 pages
Explanation:
the whole book= 7/7
He read 5/7 So 2/7 are left 28 pages = 2/7
CROSS MULTIPLICATION
x = the whole book (7/7)
2/7------------28
7/7------------x (7/7)=1
(7/7) x28 = ( 2/7)x
1x28 = (2/7)x
DIVIDE BOTH SIDES BY 2/7 = MULTIPLY BOTH SIDES BY (7/2)
(7/2)28 = x
98 = x (The whole book is 98 pages
98-28 = 70
70= (5/7) of the book
28= (2/7) of the book