Ta có sơ đồ :
số thứ 1 : 5 phan
số thứ 2 :3 phan
Số thứ 3 : 8 phan
số thứ ba là :
336 : (5 + 3 +8 ) * 8 = 168
Đáp số : 168
Tổng số phần bằng nhau là:
3+5+8=16(phần)
Giá trị 1 phần là:
336:16=21
Số ba là :
21x8=168
Đáp số:168
168 dung 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 phan tram
Bài giải
Số thứ nhất: !------!------!------!------!------!
Số thứ hai : !------!------!------!
Số thứ ba : !------!------!------!------!------!------!------!------!
Số thứ ba là: 336 : ( 3 + 5 + 8) x 8 = 168
Đáp số: 168
Gọi số thứ nhất là a, số thứ hai là b, số thứ ba là c
Theo bài ra ta có: a + b + c = 336 (1)
Ta lại có: b = 3/5 x a. Suy ra: a = 5/3 x b (2)
Ta cũng có: b = 3/8 x c. Suy ra: c = 8/3 x b (3)
Thay (2) và (3) vào (1), ta được: 5/3 x b + b + 8/3 x b = 336
5/3 x b + 3/3 x b + 8/3 x b = 336
16/3 x b = 336
b = 336 x 3 : 16 = 63
Thay b = 63 vào (3), ta được: c = 8/3 x 63 = 168
bang 168 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%
Tổng số phần bằng nhau là:
3+5+8=16 ( phần )
Số thứ ba là:
336:16x8=168